Navigating Architecture towards Net Zero

Posted on August 31, 2023 by Sean Ronnie Hill

At RISE Design Studio, we’ve always championed a sustainable approach, especially in recent years when the climate crisis is more pressing than ever. As someone who’s seen the tide change and observed the inertia in adoption, let me take you through the essence of creating low-energy, low-embodied carbon designs.

Image of Mill Hill House in North London, designed with Passivhaus Principles — ^{Mill Hill House in North London, designed with Passivhaus Principles}

1. Understanding the Net Zero Context in Construction

In 2008, the UK emerged at the forefront of environmental consciousness by introducing the Climate Change Act, a legislation aimed at steering the nation towards a more sustainable future. The vision was clear: to achieve a substantial reduction in greenhouse gas emissions, targeting an ambitious 100% cut from the levels recorded in 1990 by the time we reach 2050. This commitment reflected not only a local desire for change but also resonated with international climate accords and set a benchmark for other nations to potentially emulate.

However, navigating the path to net zero proved far more intricate than setting a numerical target. Across industries, the challenge lay in deciphering how to transition from long-standing practices, deeply entrenched in the heart of our economy, to newer, greener alternatives. The construction industry, responsible for a significant portion of the UK’s carbon emissions, was no exception. While on paper the intentions seemed promising, the underlying complexity of this transition was evident in the nation’s real-time progress.

Fast-forward to 2019, and the urgency of the situation intensified. Despite a decade having passed since the initiation of the Climate Change Act, the UK Government found itself declaring an ‘environment and climate emergency’. While some sectors showed marked improvement, others lagged, making it evident that incremental changes were insufficient to meet the monumental task at hand.

This juxtaposition of intention and outcome brings us to a pivotal juncture in our sustainable journey. The question now looms large: have we been merely sustaining — continuing practices that, although perhaps slightly improved, are essentially a perpetuation of the status quo? Or are we genuinely evolving, pushing boundaries, innovating, and truly revolutionising the way we think about and practise construction?

Addressing this question necessitates a thorough introspection of the construction sector. Are the strategies adopted merely superficial measures designed to tick boxes and fulfil statutory requirements? Or do they signify a genuine commitment to change, marking the evolution of practices that integrate sustainability at their core?

Such introspection will be fundamental as we move forward. The world is ever-evolving, and the challenges we face in the next decade might be entirely different from those we grapple with today. Thus, understanding the broader context of ‘net zero’ in construction is not just about meeting targets set in the past, but about preparing for a future that demands sustainability as its foundation. We must build not just with today in mind but with an eye on tomorrow, ensuring that our strategies, practices, and ethos are adaptable, resilient, and truly sustainable.

^{Herbert Paradise in North West London, designed with EnerPHit Principles}

2. Decoding Construction Emissions

The construction sector has always been a cornerstone of urbanisation and infrastructure development. As our cities expand and our infrastructure needs grow, so does the role of construction in shaping our environment. But with great responsibility comes the imperative to be accountable, and the statistics paint a startling picture of the sector’s impact on the environment.

2.1 The Carbon Footprint

With 45% of the UK’s carbon emissions attributed to the construction, operation, and maintenance of buildings, it’s evident that this sector is one of the primary contributors to the nation’s greenhouse gas outputs. These emissions can be traced back to various stages of a building’s lifecycle:

Materials Production: The extraction, processing, and transportation of building materials are energy-intensive processes. Concrete, for instance, is one of the most widely used construction materials, and its production is responsible for a significant portion of these emissions.
Construction Process: The activities on construction sites, from machinery operation to waste generation, contribute to the sector’s carbon footprint. Energy consumption in these phases, especially if sourced from non-renewable resources, further aggravates the emission issue.
Building Operation: Once constructed, buildings continuously consume energy, primarily for heating, cooling, and lighting. If this energy is drawn from fossil fuels, it significantly adds to the carbon load.
Maintenance & Refurbishment: Regular maintenance activities, especially those requiring extensive material inputs or energy consumption, play a part in the ongoing emissions from the built environment.

2.2 The Waste Dilemma

Waste generation is another critical area of concern. A striking 32% of landfill waste in the UK originates from construction and demolition activities. This not only represents a tremendous waste of resources but also has environmental implications. Landfills can lead to groundwater contamination, produce methane (a potent greenhouse gas), and destroy natural habitats.

Additionally, the fact that 13% of products procured for construction purposes are never used underscores a deeply entrenched inefficiency in the sector. This wastage speaks volumes about the need for better planning, forecasting, and sustainable procurement practices.

2.3 Paving the Way Forward

To effect genuine change, the construction sector must delve deeper than surface-level solutions. A systemic transformation is required, starting from the design phase right through to construction, operation, and eventual decommissioning.

Sustainable Design: Architectural and engineering designs should prioritise sustainability. This might involve the use of environmentally friendly materials, passive solar design, and energy-efficient technologies.
Resource Efficiency: By re-evaluating procurement strategies, using materials judiciously, and adopting recycling practices, the construction sector can drastically reduce waste and increase efficiency.
Transition to Clean Energy: Embracing renewable energy sources for construction operations and building functionalities can substantially mitigate carbon emissions.

In essence, the construction sector’s road to sustainability demands more than cursory changes. It’s about overhauling traditional practices, adopting innovative solutions, and committing to a vision where the built environment harmoniously coexists with the natural world.

Photo of architects discussing the design by a computer — ^{The team at RISE Design Studio}

3. Addressing Embodied Carbon: The Real Devil in the Details

When one speaks of carbon emissions in construction, the focus predominantly hovers over operational energy – the energy consumed during the usage phase of a building. However, a deeper dig reveals a far more insidious element: embodied carbon. This form of carbon refers to the greenhouse gas emissions produced during the entire life cycle of building materials, right from extraction to end-of-life. It’s the devil in the details, lurking beneath our commonly held perceptions of construction’s environmental impact.

3.1 Defining Embodied Carbon

Embodied carbon can be split into two primary categories:

Upfront Embodied Carbon: This encompasses emissions from the extraction, processing, manufacture, and transportation of materials used in construction. These emissions occur before the building even comes into existence.
End-of-life Embodied Carbon: Emissions in this category arise from the repair, renovation, deconstruction, and disposal processes after the construction phase.

Both forms of embodied carbon are equally vital, and together they account for a significant proportion of a building’s total carbon footprint.

3.2 The Overshadowed Emissions

There are several reasons why embodied carbon is often overlooked:

Eclipsed by Operational Carbon: The ongoing energy use in buildings, particularly in heating, cooling, and lighting, often overshadows embodied carbon because of its recurrent and visible nature.
Complexity in Measurement: Calculating embodied carbon is challenging due to the varied lifecycle of materials, differences in transportation methods, and the myriad processes involved in material creation.
Lack of Awareness: A comprehensive understanding of embodied carbon is still nascent in many industry circles. As a result, its importance is often diminished in mainstream discussions.

3.3 Unveiling the Hidden Impact

Several construction practices and phases contribute to the stealthy rise of embodied carbon:

Material Choice: Materials like concrete and steel, while sturdy and reliable, come with a hefty carbon price tag due to their manufacturing processes.
Transportation: Long supply chains and the heavy machinery involved in transporting materials amplify the carbon footprint.
Construction Techniques: Traditional construction methods might not always be the most carbon-efficient.
Maintenance and Refurbishment: The frequent replacement of components, the use of non-sustainable materials for repairs, and inefficient restoration methods add to the carbon load.
Waste Management: Inadequate recycling and reuse practices during deconstruction can lead to unnecessary emissions during waste disposal.

3.4 Charting a New Course

Addressing embodied carbon necessitates a multi-pronged approach:

Material Innovation: Research and development into low-carbon alternatives for traditional building materials can significantly reduce upfront emissions.
Efficient Supply Chains: Streamlining transportation and sourcing materials locally can diminish the carbon emissions from logistics.
Lifecycle Thinking: Architects, engineers, and builders need to adopt a lifecycle perspective, considering the environmental impact of materials from cradle to grave.
Education and Advocacy: Spreading awareness about embodied carbon and its implications is crucial. Only with widespread knowledge can industry-wide changes be effected.

In summary, while operational energy remains a critical area of focus, a holistic approach that also accounts for embodied carbon is indispensable. Recognising and addressing this hidden devil in the details is imperative for a truly sustainable construction sector.

4. Redefining Materials: Beyond Steel and Concrete

The skyline of our modern cities, with its towering skyscrapers and sprawling infrastructure, tells a tale of steel and concrete, two materials that have become synonymous with construction. Their strength, durability, and versatility have made them the default choice for most construction projects. Yet, as we delve deeper into the 21st century, we are confronted with the undeniable environmental costs these materials incur. But with companies like Solidia transforming the very essence of such materials, and with the burgeoning rise of alternative construction resources, we might be on the cusp of a materials revolution.

4.1 The Environmental Weight of Steel and Concrete

Steel and concrete, while architecturally transformative, have environmental repercussions:

Carbon-Intensive Production: The production of steel requires the smelting of iron at high temperatures, usually achieved through coal, releasing a significant amount of CO2. Similarly, the production of cement, a key component of concrete, is responsible for approximately 8% of global carbon dioxide emissions.
Resource Depletion: Large quantities of raw materials, such as iron ore for steel and limestone for cement, are extracted, which impacts ecosystems and depletes finite resources.
Waste Production: The production processes, particularly for steel, result in by-products and waste, which can be challenging to manage.

4.2 Pioneering Change: The Solidia Example

Solidia’s approach exemplifies how innovation can alter the landscape of traditional materials. By changing the chemical process in cement production, Solidia not only reduces CO2 emissions but also uses CO2 in the curing process of concrete. Such advancements showcase the potential for revamping old practices for a greener future.

4.3 Beyond the Familiar: Exploring Alternative Materials

While innovations in concrete and steel are welcome, diversifying our materials palette is crucial:

Timber: Modern engineered timber products, like cross-laminated timber (CLT), offer strength comparable to traditional materials but with a fraction of the carbon footprint. Trees, as they grow, sequester carbon, making timber a carbon-negative material.
Bamboo: Rapidly renewable and incredibly sturdy, bamboo can be a sustainable alternative for various construction needs, especially in regions where it naturally grows.
Hempcrete: Made from the hemp plant’s woody core and a lime-based binder, hempcrete is a lightweight, insulating, and carbon-sequestering material.
Mycelium: This fungal material is organic, fully compostable, and can be grown into various moulds, making it a potential insulator or structural element.
Recycled and Reclaimed Materials: Utilising materials from demolished structures or repurposing waste products can drastically cut down on emissions from new material production.

4.4 The Road Ahead: Integration and Acceptance

The future of construction doesn’t necessarily lie in abandoning steel and concrete altogether but in integrating them with a broader set of sustainable materials. Challenges remain:

Regulations and Standards: New materials need to meet safety and performance standards, requiring rigorous testing and approvals.
Industry Mindset: Long-held beliefs and practices need to be reconsidered, which requires education, training, and a willingness to innovate.
Cost Implications: Some sustainable materials are currently more expensive than their traditional counterparts, making them less attractive for budget-tight projects.
Supply Chain Development: New materials necessitate new supply chains, which can pose logistical challenges initially.

However, with the environmental imperative clearer than ever, the shift towards more sustainable materials is not just desirable but essential. As the construction industry redefines its relationship with materials, it takes a significant step towards a more sustainable, green, and innovative future.

Image of Red Arches House in Kensal Rise, North West London, designed to Passivhaus Standards — ^{Red Arches House in Kensal Rise, North West London, designed to Passivhaus Standards}

5. Embracing Timber: An Old Solution to a New Problem

Timber, once the primary material in many traditional construction practices, seemed to have been overshadowed by the rise of steel and concrete in modern times. However, as the quest for sustainable construction materials becomes imperative, timber is making a significant comeback. Central to this resurgence is Cross-Laminated Timber (CLT), a modern engineered wood product that is redefining the construction landscape. Pioneering firms such as RISE Design Studio and Waugh Thistleton are at the forefront of this timber revolution, exemplifying the perfect amalgamation of tradition, innovation, and sustainability.

5.1 The Science of Cross-Laminated Timber (CLT)

CLT is not just any regular wood. It’s a multi-layered wood panel made by stacking layers of lumber orthogonally and bonding them with structural adhesives. This unique structure provides CLT with:

Strength: Comparable to traditional building materials, making it suitable for multi-storey structures.
Fire Resistance: The dense, compact layers char slowly, providing a natural barrier to fire.
Thermal Efficiency: Timber’s natural insulating properties make CLT structures energy-efficient.

5.2 The Environmental Advantage

Beyond its structural merits, CLT stands out for its sustainability:

Carbon Sequestration: Trees absorb carbon dioxide as they grow. Even when transformed into CLT, the carbon remains locked in, making timber a carbon-negative material.
Renewability: Forests, if managed responsibly, can provide a continual source of timber without depleting the Earth’s resources.
Reduced Waste: CLT panels can be precision-cut off-site, leading to minimal waste during construction.

5.3 Projects in the Limelight: Dalston Works

The transformative power of timber becomes evident when one examines architectural marvels like Dalston Works:

Dalston Works: Showcasing the versatility of timber, this project intertwines modern design with sustainable practices. Its distinctive appearance, combined with energy efficiency, makes it a beacon of future-forward architecture.

5.4 Timber’s Potential in Modern Architecture

The adaptability of timber is not just about its inherent properties but also about the innovative minds that mould it. Leading design studios are:

Pushing Design Boundaries: Exploring intricate forms, curves, and overhangs previously thought challenging with timber.
Integrating with Other Materials: Combining timber with glass, steel, or concrete to produce hybrids that maximise the strengths of each material.
Exploring Prefabrication: Taking advantage of timber’s suitability for off-site construction to enhance efficiency and reduce construction times.

5.5 The Path Forward

While the merits of timber, particularly CLT, are compelling, it’s essential to approach timber construction with a balanced perspective. Responsible forestry, innovative design, and public perception are areas that require attention. With the right commitment, however, timber can indeed bridge the gap between our architectural ambitions and our environmental responsibilities.

In a world grappling with environmental challenges, timber’s re-emergence in the construction arena offers a glimmer of hope. By marrying the old and the new, it serves as a poignant reminder that sometimes, solutions to our most pressing issues can be found by looking back even as we march forward.

6. Debunking the Myths: Timber and Safety

The catastrophic events at Grenfell Tower undoubtedly cast a dark shadow over the use of certain materials in construction, leading to heightened concerns around fire safety. While the emphasis on safety is necessary and commendable, it’s vital to ensure that accurate information drives public perception and policy decisions. One such material under scrutiny is timber. However, it’s essential to separate fact from fiction, particularly when considering the benefits and risks associated with timber, especially Cross-Laminated Timber (CLT).

6.1 Timber: The Burning Myths

Combustibility: Timber is often viewed as a highly flammable material. While it’s true that timber can burn, its combustion properties, especially in thick sections like those in CLT, are predictable. When exposed to fire, timber forms a protective char layer that insulates the internal layers, slowing down the burning rate.

Fire Spread: Another misconception is that timber can cause rapid fire spread. In reality, CLT panels, due to their compactness, burn at a much slower rate than expected, often providing more resistance than some other conventional materials.

6.2 The Science Behind Timber Fire Safety

Several factors determine timber’s behaviour in fires:

Density: Denser woods tend to have a slower charring rate, providing an added layer of protection.
Moisture Content: Dry timber is more prone to ignition, but once a char layer forms, moisture content has less influence on the burning rate.
Thickness: Thicker CLT panels take longer to burn through, offering extended protection in the event of a fire.

6.3 Sustainable Forestry: A Double Boon

Well-managed timber forests play a dual role:

Endless Raw Material Supply: With sustainable forestry practices, we can ensure a continuous supply of timber without degrading our environment.
Carbon Sequestration: As trees grow, they absorb carbon dioxide, making forests a vital carbon sink. By turning these trees into CLT panels, we lock in that carbon, further reducing our carbon footprint.

6.4 Regulatory Response: Ensuring Safety

While the inherent properties of timber offer fire resistance, it’s paramount that the regulatory environment also reflects best practices:

Strict Building Codes: These should emphasise fire safety regardless of the construction material.
Regular Inspections: Buildings made from timber should undergo frequent safety inspections to ensure they remain up to standard.
Fire Safety Education: Educating both the construction industry and the public on the safe use of timber can alleviate unfounded fears.

6.5 Beyond Safety: The Holistic Benefits of Timber

While safety is paramount, it’s also essential to view timber in a broader context. Its sustainability, aesthetic appeal, and overall contribution to well-being make it a material that offers benefits well beyond just structural properties.

In conclusion, while the Grenfell tragedy rightly makes us question and re-evaluate our construction practices, it’s crucial that our responses are informed and balanced. Timber, especially in its engineered forms like CLT, presents an opportunity to build sustainably and safely. By debunking myths and investing in robust safety measures, we can ensure that timber continues to play a pivotal role in our built environment.

Image of Imran and Bethany discussing proposals for a sustainably driven residential project in South London — ^{Imran and Bethany discussing proposals for a sustainably driven residential project in South London}

7. Beyond Conventional Wisdom: Challenging Green Standards

In recent times, the race towards a sustainable future has led to a surge of “green” labelled products and construction methodologies. While many of these standards have paved the way for increased environmental awareness, the challenge now lies in discerning between what is truly sustainable and what might merely be ‘greenwashed’ or superficially eco-friendly.

7.1 The Green Mirage: Unmasking Greenwashing

The term ‘greenwashing‘ describes the process by which organisations misleadingly promote their products, aims, or policies as environmentally friendly when, in reality, they might not be. In the realm of construction, this can manifest in several ways:

Vague Claims: Terms like ‘eco-friendly’ or ‘all-natural’ without clear definitions or contexts can be misleading.
Hidden Trade-offs: A product might be marketed as green based on a single environmentally friendly attribute, overshadowing other potentially harmful impacts.
Lesser of Two Evils: Positioning a slightly ‘greener’ version of a notoriously unsustainable product as the ideal choice.

7.2 Evaluating the True Impact: Life Cycle Assessments

To genuinely gauge the sustainability of a material or method, it’s crucial to perform a Life Cycle Assessment (LCA). This comprehensive review examines the environmental impact of a product throughout its entire lifespan – from raw material extraction to disposal.

Cradle-to-Grave: This approach examines the total environmental impact from material extraction to the end of the product’s life.
Cradle-to-Gate: This evaluates the environmental implications from material extraction up to the point where the product leaves the production facility.
Cradle-to-Cradle: This considers the entire product life cycle but with a focus on recycling or repurposing materials, rather than disposal.

7.3 Beyond Materials: Holistic Sustainable Practices

While the materials used play a significant role, true sustainability encompasses a broader approach:

Design Philosophy: Architectural designs that incorporate passive solar heating, natural ventilation, and other green principles can significantly reduce a building’s environmental footprint.
Operational Efficiency: The way buildings are utilised and maintained can dramatically impact their overall sustainability.
Community Engagement: Local sourcing of materials and involving the community in construction projects can foster sustainable development and social responsibility.

7.4 Setting the Bar Higher: Next-Generation Green Standards

For the construction industry to evolve sustainably, it’s essential to challenge and refine the green standards regularly:

Transparent Certifications: Clear criteria and rigorous third-party verifications for green labels can prevent misleading claims.
Innovative Benchmarks: Encouraging the research and adoption of innovative solutions can pave the way for more robust green standards.
Stakeholder Involvement: Engaging industry experts, environmentalists, and the public can ensure diverse perspectives shape sustainability standards.

7.5 Embracing Authentic Sustainability

The path to a genuinely sustainable future requires a shift in mindset. Rather than merely ticking boxes or achieving green labels, the construction industry should be guided by an inherent commitment to minimising environmental harm and enhancing societal well-being.

In conclusion, while current green standards have laid the essential groundwork, the next phase of sustainable construction must challenge, refine, and elevate these benchmarks. Only by aiming higher and demanding authentic sustainability can we hope to construct a future that’s not just built on solid foundations, but is also harmoniously intertwined with the environment.

8. The Dawn of Sustainable Materials and Technologies

In the past, the construction industry primarily revolved around traditional materials and methods, driven by tried-and-tested techniques. However, as environmental concerns have heightened, there’s been a transformative shift towards more sustainable options. Universities, startups, and leading businesses are pioneering new materials and technologies that not only challenge the status quo but promise a more sustainable future without compromising on performance.

8.1 Plant-Based Insulation: A Breath of Fresh Air

Washington State University has been at the forefront of developing plant-based insulation. Unlike conventional insulation, which often contains synthetic and potentially harmful components, plant-based alternatives offer:

Reduced Carbon Footprint: Derived from renewable resources, the production of plant-based insulation emits fewer greenhouse gases.
Health Benefits: Natural materials reduce the risk of off-gassing, which is associated with various health concerns.
Biodegradability: At the end of its life cycle, plant-based insulation can degrade naturally, avoiding the landfill challenges posed by synthetic counterparts.

8.2 BioMason: Building the Future, One Brick at a Time

BioMason’s groundbreaking approach involves “growing” bricks from organic material. This innovative method:

Eliminates the Need for High-Temperature Kilns: Traditional brick-making is energy-intensive, often requiring vast amounts of fossil fuels.
Reduces CO2 Emissions: BioMason’s process sequesters carbon dioxide, thus actively reducing the amount of CO2 in the atmosphere.
Offers Design Versatility: As they are grown, these bricks can be customised for different textures, strengths, and sizes.

8.3 StoneCycling: Recycling for Robust Construction

StoneCycling has revolutionised brick manufacturing by using waste materials. Their method:

Diverts Waste from Landfills: By upcycling waste, StoneCycling reduces the strain on landfills.
Diverse Aesthetics: The use of various waste materials results in a unique array of colours and textures for each brick.
Conserves Natural Resources: As the bricks are made from recycled materials, the need for virgin raw materials is drastically reduced.

8.4 The Larger Landscape: Beyond Bricks and Insulation

While the aforementioned technologies are noteworthy, the horizon of sustainable construction materials is vast:

Hempcrete: Made from hemp, lime, and water, Hempcrete provides excellent insulation and is carbon-negative.
Mycelium Composites: Fungi-based materials are not only sustainable but offer unique structural and insulation properties.
3D Printing: This technology allows for precise material use, reducing waste and allowing for the use of recycled or alternative materials in construction.

8.5 The Promise of Tomorrow

The innovations led by institutions like Washington State University and companies such as BioMason and StoneCycling are just the tip of the iceberg. With a growing emphasis on sustainable development, research and investments in this arena are set to soar.

In closing, the dawn of sustainable materials and technologies is not a distant dream but a burgeoning reality. As we continue to explore and embrace these alternatives, we’re not only crafting structures but also moulding a more sustainable, environmentally conscious future.

^{The Avenue Brick House in Pinner, North London}

9. Shaping Tomorrow: Legislation or Nature’s Reckoning?

The push and pull between human-made rules and nature’s undeniable truths have long dictated the way we approach our environment. As the construction industry stands at the crossroads of modernity and sustainability, the driving factors for change have never been more apparent. The decision before us is clear: either adapt proactively through legislation or react defensively against the increasingly severe consequences of climate change.

9.1 The Power of Legislation

Governmental mandates can act as the very catalyst the industry needs to propel towards sustainable change.

Setting Clear Standards: By establishing quantifiable benchmarks for sustainability, governments can ensure a baseline level of environmental responsibility.
Incentivising Green Practices: Tax reliefs, grants, or reduced permit fees for sustainable construction can encourage developers to go green.
Educating the Masses: State-funded programmes can raise awareness about the significance of sustainable construction and its long-term benefits.

9.2 The Wrath of Nature

Ignoring the environment’s cues is no longer an option. Nature’s reckoning is evident in the form of:

Natural Disasters: Increasingly severe weather events, from floods to heatwaves, highlight the immediate need for resilient and sustainable architecture.
Resource Depletion: The scarcity of traditional construction materials is pushing the industry to seek sustainable alternatives.
Ecological Impact: Loss of biodiversity and degraded landscapes are sobering reminders of the toll our construction choices can have on local ecosystems.

9.3 Advocacy in Design

As architects, engineers, and builders, industry professionals are in a unique position to influence sustainable change.

Innovative Blueprints: By prioritising sustainable materials and methods in designs, the industry can pave the way for a new construction era.
Client Engagement: Engaging in open dialogues with clients about the benefits and necessity of green construction can make a substantial difference.
Collaborative Efforts: Partnerships with environmental experts and conservationists can enhance the industry’s understanding and implementation of sustainable practices.

9.4 A Collective Vision

The journey to sustainability is not a solo endeavour but a collective vision. Every stakeholder, from the labourer on the ground to the investor in the boardroom, plays a pivotal role.

Empowering Workers: Training programmes can equip construction workers with the knowledge and skills to implement sustainable practices effectively.
Investment in Research: Financial backing for research into sustainable materials and construction techniques can unlock new possibilities.
Community Involvement: Encouraging community input in construction projects can lead to more environmentally friendly and socially responsible outcomes.

9.5 The Path Forward

While both legislation and nature’s reckoning are formidable forces, the true power lies in our hands. Through conscious choices, unyielding commitment, and a shared vision, the construction industry can and must shape a sustainable tomorrow. The stakes are high, but so too are the rewards: a world where buildings not only serve their occupants but also honour the environment they inhabit.

Image of Douglas House in Kensal Rise, North West London, designed with EnerPHit principles — ^{Douglas House in Kensal Rise, North West London, designed with EnerPHit principles}

10. The Path Forward: From Within the Industry

In the throes of an environmental revolution, the construction sector stands at the vanguard of change. While external pressures, from legislation to market demand, play a role, it’s the industry insiders who hold the key to reshaping its future. For the architects, builders, and designers at the helm, leading the charge towards a net-zero future is not only a responsibility but a calling.

10.1 Embracing the In-House Vanguard

Leading by Example: Key industry players should exemplify best practices, both in their designs and on-site operations.
Continuous Education: Regular training and workshops can be conducted to update industry professionals on the latest sustainable methodologies and technologies.
Empowering the Next Generation: Mentorship programmes and internships centred on green construction can foster an environment of growth and knowledge exchange.

10.2 Fostering Collaboration

Open Dialogue: Platforms for discussion can be established, enabling professionals from different disciplines to share insights, troubleshoot issues, and brainstorm innovative solutions.
Partnerships with Academia: Collaborative efforts with universities can lead to research-driven solutions, paving the way for groundbreaking sustainable techniques.
Engagement with Suppliers: Close ties with material suppliers can foster the development of eco-friendly products tailored to the industry’s specific needs.

10.3 Financing the Green Revolution

Green Investment: Industry leaders can push for more financial backing into sustainable construction projects, ensuring their viability and profitability.
Grants and Incentives: Companies can establish grant systems for startups and projects that emphasise sustainability, creating a positive feedback loop of innovation.
Cost-Benefit Analysis: By showcasing the long-term financial and environmental benefits of sustainable construction, the industry can encourage stakeholders to back such projects.

10.4 Nurturing Innovation

R&D Focus: Companies can set aside dedicated funds and resources for research and development, promoting the creation of novel solutions.
Rewarding Creativity: Internal competitions, awards, and recognitions can be established to motivate employees to think outside the box.
Adopting Technology: Embracing technological advancements, such as Building Information Modelling (BIM) and green tech, can drive efficiency and sustainability.

10.5 The Ethos of Change

At the heart of this monumental shift lies a change in ethos. The construction industry needs to move away from the short-term, profit-driven mindset to one that values long-term sustainability and societal benefit. This ethos, while business-centric, should echo the broader societal push for environmental stewardship.

In Conclusion

Our commitment to a sustainable future in the construction sector is a marathon, not a sprint. It demands a holistic reimagining of processes, priorities, and perspectives. By forging ahead with resolve, unity, and vision, the industry can make the dream of a net-zero future an everyday reality. And in this collective endeavour, it’s not the distant policymakers or detached critics who will drive the change, but the passionate architects, builders, and designers at the very heart of the industry.

If you would like to talk through your project with the team, please do get in touch at mail@risedesignstudio.co.uk or give us a call on 020 3290 1003

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Redefining Sustainable Architecture: The Pioneering EnerPHit Standard

Posted on August 20, 2023 by Sean Ronnie Hill

Given the pressing need for low-energy and low-embodied carbon designs, the industry has seen a growing emphasis on standards like Passivhaus for new builds. But what about the vast number of existing buildings that do not meet these criteria? Enter EnerPHit.

View of the dormer at Douglas House designed by RISE Design Studio in Kensal Rise NW London, designed following EnerPHit principles — ^{Douglas House by RISE Design Studio in Kensal Rise NW London, designed following EnerPHit principles}

1. The Architect’s Evolution: From New Builds to Retrofits

When I began my career 20 years ago, the primary emphasis was on new-build projects. The exciting prospect of constructing new structures from the ground up was the norm. However, as the years went by and the urgency of addressing climate change became more evident, the focus started shifting towards how we can also make older structures more energy efficient.

2. The Passivhaus Standard: Setting the Benchmark

The Passivhaus Standard came as a breath of fresh air, setting the bar high for thermal performance in new structures. It was designed with a primary focus on new builds, where every aspect of the building, from its fabric to its structure, was chosen to enhance thermal performance. As architects, we appreciated the rigorousness of the standard, but soon realised its limitations for retrofit projects.

3. The Rise of EnerPHit: Answering the Retrofit Challenge

Understanding that the high standards of Passivhaus weren’t always achievable for retrofit projects, the EnerPHit standard was born. Recognised by the Passivhaus Institute, EnerPHit acts as a bridge, allowing older buildings to be renovated closer to the stringent Passivhaus standards. It considers the nuances and challenges of retrofitting, especially when it comes to fixed aspects of existing buildings.

4. Delving Deeper: Key Elements of the EnerPHit Retrofit

EnerPHit doesn’t merely provide a broad-brush approach. It specifically addresses several critical elements in older buildings, including:

Improved fabric performance
Overall limit on energy demand and emissions
Comfort and health outcomes
Closure of energy performance gap

By focusing on these aspects, EnerPHit ensures that older properties can achieve energy efficiency comparable to their newer counterparts.

5. Why the Shift Towards EnerPHit is More Important Than Ever

In the wake of the UK government’s 2019 pledge to achieve net-zero carbon emissions by 2050, the construction industry has undergone a paradigm shift. While products like Green Life Building’s SIP panels are emerging as favourites for new builds, the importance of retrofitting cannot be overstated. It’s not just about constructing new energy-efficient buildings; it’s also about transforming our existing ones.

6. The Practical Implications: Achieving EnerPHit Standards

Using technologies such as SIP panels, which can be retrofitted into existing properties, buildings can achieve the coveted EnerPHit standards. This not only reduces heating energy requirements and carbon dioxide emissions by up to 90% compared to traditional structures but also offers a plethora of benefits to homeowners and businesses alike.

7. The Tangible Benefits of the EnerPHit Retrofit

At our studio, we’ve observed a wide range of advantages for properties renovated to the EnerPHit standards:

Significant reduction in energy bills
Enhanced energy security
Comfortable and consistent living conditions
An increase in property value
A notable reduction in carbon footprint

8. More Than Just Numbers: The Comfort of EnerPHit Retrofits

It’s essential to highlight that EnerPHit doesn’t just mean statistical energy savings. For those residing or working within, it translates to a tangible increase in comfort. Expect consistent and ambient air temperatures, draft-free spaces, controlled humidity, and an environment free from surface condensation and mould growth.

9. The Architect’s Perspective: Embracing the Change

As someone who has been a part of this industry for two decades, adopting and promoting EnerPHit has been a transformative experience. It’s not just about being in line with legislation or industry standards; it’s about reshaping our architectural landscape, making it more sustainable and future-ready.

10. The Path Ahead: Retrofitting for a Sustainable Future

As we move forward, retrofitting will play a pivotal role in shaping the future of sustainable architecture. By embracing standards like EnerPHit, we’re not just upgrading buildings; we’re ushering in a new era of responsible and visionary architectural design.

In conclusion, the EnerPHit standard offers a beacon of hope for older structures, ensuring they are not left behind in the race towards a sustainable future. By marrying contemporary design with stringent energy efficiency standards, we can create buildings that stand the test of time, both in terms of design and functionality.

If you would like to talk through your project with the team, please do get in touch at mail@risedesignstudio.co.uk or give us a call at 020 3290 1003

RISE Design Studio Architects company reg no: 08129708 VAT no: GB158316403 © RISE Design Studio. Trading since 2011.

Housing Retrofit and the Quest for Airtightness: An Architect’s Guide

Posted on August 14, 2023 by Sean Ronnie Hill

What is airtightness?

Here, I aim to give you a deeper understanding of what airtightness is, combining theory with the practicalities we’ve encountered working on the many low-energy retrofit and new build projects we’ve completed.

Image of Proclima Intello tape used for airtightness on this timber frame house — ^{Proclima Intello tape uses for airtightness on this timber frame house}

Chapter 1: Introduction, The Airtightness Imperative

In today’s age of sustainability, the topic of energy efficiency has steadily climbed the agenda of architects, builders, and homeowners alike. Notably, airtightness has emerged as a paramount concern, given its direct correlation with energy loss. Older homes, with their dated construction methods and less effective materials, have historically struggled with energy loss due to air leakage. However, as construction methods have modernised, the magnitude of the problem has only grown more apparent.

1.1 The Evolution of Housing and Energy Loss

To understand the significance of airtightness in contemporary construction, we must first look back. Historically, the construction of homes was more ‘breathable’, primarily due to the materials and techniques employed. These houses, while charming, often had gaps, cracks, and other points of air leakage. The result? Approximately 20% of energy, predominantly from space heating, would be lost due to these imperfections.

However, as society became more environmentally conscious, the methods of construction evolved. Modern homes became insulated havens with double or triple-glazed windows, improved wall insulation, and advanced heating systems. As these improvements reduced other methods of heat loss, the proportion of energy loss attributed to ventilation drastically increased. Today, it’s estimated that ventilation contributes to 35-40% of a home’s energy loss.

1.2 The Modern Paradigm

While our forebears might have been more accepting of a drafty home, modern homeowners are not. Rising energy costs, the push for green technologies, and the demand for energy-efficient homes have highlighted the importance of airtightness. It’s no longer sufficient to slap on a layer of insulation and call it a day. Every joint, seam, and intersection in a building needs scrutiny.

1.3 The Comprehensive Approach to Airtightness

A comprehensive approach to airtightness doesn’t simply focus on sealing gaps. It requires a multi-faceted strategy that includes:

Material Selection: Using advanced materials that inherently reduce air leakage.
Construction Techniques: Employing methods that emphasise the airtight sealing of a building’s envelope.
Mechanical Systems: Implementing controlled ventilation systems, ensuring fresh air intake without energy loss.
Regular Maintenance and Checks: As buildings settle and age, potential problem areas might emerge. Routine checks ensure that a building remains as airtight as the day it was constructed.

In conclusion, as the architectural and construction industries continue to progress, the airtightness imperative will remain central to the dialogue. The benefits, ranging from reduced energy costs to a lower carbon footprint, make it clear that this is not just a trend but a necessary evolution in the way we build and inhabit spaces.

image of A typical Victorian property in Queen's Park, North West London — ^{A typical Victorian property in Queen’s Park, North West London}

Chapter 2: What is Airtightness and Why is it Crucial?

The notion of airtightness might initially conjure images of sealed containers or vacuum chambers. However, when it comes to the built environment, this term carries a nuanced significance. Airtightness has come to the forefront of architectural discourse, not merely as a buzzword, but as an indispensable criterion for modern design.

2.1 Defining Airtightness

At its core, airtightness speaks to a building’s capacity to prevent unintended air exchange with its surroundings. This doesn’t mean a space void of fresh air, but rather, an environment where the inflow and outflow of air are meticulously controlled. This is measured in terms of air permeability, which quantifies the volume of air (in cubic metres) that leaks per hour through each square metre of the building’s external envelope under specific test conditions.

2.2 The Implications of Air Leakage

When a building is not airtight, it falls prey to the unpredictable whims of the environment. During colder months, warmth from the interior might escape, while in summer, the heat could intrude. This inconsistent interchange:

Compromises Indoor Comfort: Rooms may feel draughty or have fluctuating temperatures.
Increases Energy Consumption: As heating or cooling systems work overtime to compensate for the loss or gain of heat, energy usage escalates.
Elevates Utility Costs: With energy consumption on the rise, utility bills can also see a noticeable uptick.

2.3 Airtightness: A Pillar of Modern Architecture

For an avant-garde design studio such as ours, the principles of airtightness are not just checkboxes in a compliance sheet. They represent the ethos of 21st-century architecture:

Sustainability: With the global push towards eco-consciousness, reducing the carbon footprint of buildings has become paramount. Airtight buildings play a significant role in this pursuit.
Innovation in Design: Modern architecture seeks not just to appease the eye but also to push the boundaries of what’s possible. Incorporating airtightness solutions challenges designers to innovate and redefine building norms.
Holistic Building Performance: Contemporary design recognises that aesthetics and functionality are two sides of the same coin. Airtightness, thus, contributes to a building’s overall performance, enhancing occupants’ comfort and well-being.

2.4 Ensuring Airtightness: An Integral Phase

Ensuring a building is airtight is not an afterthought—it’s an intrinsic part of the design and construction process. This involves:

Detailed Designing: Right from the drafting table, potential air leakage points are identified and mitigated.
Material Specification: Using advanced membranes, sealants, and insulation which help in achieving the desired airtightness levels.
On-site Verification: Employing tools like blower door tests to measure and verify the airtightness of a constructed space.

In summary, as the construction landscape evolves, understanding and emphasising airtightness remains pivotal. It is not just about conforming to standards but sculpting spaces that resonate with the needs and aspirations of our times.

Image showing airtightness membranes and specialised seals around ductwork and wires — ^{01 Taping of membrane overlapping to underside of ceiling / 02 Airtightness taping around joist ends / 03 Airtightness membrane at the underside of a ceiling with taping around web-joists and other junctions / 04 Airtight membranes installed prior to the installation of internal studwork 05 Specialised seals around ductwork 06 Specialised seals around penetration for wires. Image credit: Passivehouse Plus}

Chapter 3: Modern vs. Older Homes: A Comparison

When delving into the domain of building construction and airtightness, it’s tempting to believe that advancements in technology and design inherently make modern homes superior to their older counterparts in every aspect. However, this isn’t always the case, especially when examining airtightness. Contrary to popular belief, some contemporary homes might fall short in this arena when compared to older structures.

3.1 The Architectural Evolution Over Time

The architectural journey, over decades, has been marked by evolving aesthetic preferences, changing materials, and innovations in construction techniques. Historically:

Older Homes: They were often constructed with dense, solid materials, like brick and stone, which naturally provided a certain level of airtightness. The simpler design patterns, with fewer joints and breaks in the structure, minimised air leakage points. Ventilation was usually provided by natural draughts through less refined windows and doors.
Modern Homes: These epitomise a blend of complex designs, large glazed areas, and a vast array of materials. While they offer numerous advantages, the complexity can introduce numerous potential points of air leakage if not meticulously managed.

3.2 The Paradox of Modern Construction

Modern buildings are not inherently flawed, but the challenges they pose in terms of airtightness include:

Varied Workmanship: The quality of construction can fluctuate significantly due to diverse workmanship standards, potentially creating inconsistent airtightness levels across different buildings or even different parts of the same building.
Complex Assemblies: Modern homes often feature intricate design elements—such as larger windows, complex junctions, and multiple material transitions—that can introduce vulnerabilities if not sealed appropriately.
Rapid Construction: The drive to complete buildings quickly can sometimes lead to an oversight in ensuring airtightness.

3.3 Lessons from the Past

While older homes might lack many of the modern amenities and technological advancements, their approach to airtightness, albeit unintentional, offers lessons:

Simplicity: Fewer joints and breaks mean fewer potential leak points. Modern designs can aim for a balance between aesthetic complexity and airtight simplicity.
Use of Natural Materials: Traditional construction often leveraged materials that inherently provided good insulation and airtight properties. Revisiting some of these materials could be beneficial.

3.4 Striking the Right Balance

For the forward-thinking homeowner, architect or builder, the key lies not in choosing between old and new but in harmoniously blending the strengths of both:

Informed Design Choices: Marrying the aesthetic appeal of modern designs with principles that enhance airtightness.
Quality Control: Ensuring that the workmanship standards are consistently high across all stages of construction.
Continuous Innovation: Integrating new technologies and materials that offer better airtightness solutions without compromising on design.

In conclusion, while the dichotomy between modern and older homes presents unique challenges, it also provides a rich tapestry of insights. Embracing the best of both worlds can lead to spaces that are not only visually compelling but also functionally superior in terms of airtightness.

Image showing diagram showing Windtight and Airtight layers as well as thermal bridge free construction and super insulation — ^{Diagram showing Windtight and Airtight layers as well as thermal bridge free construction and super insulation}

Chapter 4: Current Standards and Achievements

The realm of building and construction, particularly when it comes to airtightness, is a dynamic field. Regulations and standards are set to maintain a certain quality level and ensure energy efficiency. Yet, as the industry evolves, so does the challenge of consistently meeting these established standards. The Building Regulations 2022 is a testament to such an ambition, but how does it fare in practical scenarios?

4.1 An Overview of Building Regulations 2022

The Building Regulations 2022 is a cornerstone for construction standards in the UK:

Airtightness Standard: One of its regulations is the airtightness of buildings, setting the bar at 10 m3/hr/m2. This benchmark is founded on the principles of energy conservation, comfort, and sustainability.
Part L1A of the Building Regulations stipulates the baseline requirements for testing at a threshold value of 10m³/hr/m². However, the rate often required to achieve the TER is considerably lower.
In most designs, values ranging from 4 to 6m³/hr/m² are utilised. With meticulous attention to the details during the construction phase, these rates can be easily met. Once the construction is finalised, the actual air leakage rate is ascertained through on-site testing.
High-performance constructions, like Passivhaus homes, often consistently record rates lower than 1m³/hr/m².
All new homes must undergo testing upon completion, with two specific exceptions: 01: If an identical construction has been completed by the same builder within the previous year and has satisfactorily passed an airtightness test. 02: When a high default value of 15m³/hr/m² is applied in the SAP assessment.
If you wish to circumvent the uncertainty of on-site testing, an air leakage rate of 15 can be selected. This rate is akin to having a sizeable window left open during the test, thus eliminating the need for testing entirely. However, this would necessitate substantial countermeasures like extra-thick insulation amongst others.

4.2 Dissecting the Survey Findings

A survey targeting 100 contemporary homes brought some revealing insights:

Startling Figures: While standards project a certain level of airtightness, approximately 33% of these homes didn’t even achieve the set benchmark. Such a deviation is a cause for concern, indicating a potential disconnect between regulatory standards and on-ground execution.
Variability in Construction: Even within modern constructions, there was a vast variance in airtightness levels. While some exceeded the standards, others lagged woefully behind.

4.3 Impediments to Achieving the Standard

Several factors contribute to this noticeable disparity:

Knowledge Gap: Not all builders and contractors might be fully versed in the nuances of the airtightness standards, leading to unintentional oversights during construction.
Workmanship Consistency: As previously discussed, variability in workmanship quality can result in different airtightness levels.
Cost Factors: Achieving high levels of airtightness might involve additional costs in terms of materials and labour. Some builders might cut corners to stay within budgets.
The Complexity of Modern Designs: Advanced architectural designs can inadvertently introduce challenges in maintaining airtightness.

4.4 The Way Forward: Bridging the Gap

While the current scenario isn’t entirely bleak, there’s an evident need for course correction:

Awareness Campaigns: Construction industry stakeholders, including architects and builders, need periodic updates and training on the importance and techniques of achieving airtightness.
Robust Inspection Mechanisms: Regular and rigorous inspections during and after construction can help identify potential lapses and rectify them timely.
Feedback Loops: Learning from projects that failed to meet the standards can provide invaluable insights for future constructions.
Rethinking Standards: It might be beneficial to revisit the standards themselves periodically, ensuring they are in sync with current technologies, materials, and construction practices.

In summation, while standards like the Building Regulations 2022 provide a fairly solid foundation (but does need to be improved considerably due MVHR only being efficient when airtightness is below 7 m3/hr/m2), their real-world implementation demands continuous monitoring and adaptation. Only through concerted efforts from all industry stakeholders can the aspiration of optimal airtightness in every home be achieved and improved.

^{Airtightness test at our Red Brick House in Willesden, North West London}

Chapter 5: Key Areas of Concern: Common Air Leakage Points

When aiming for optimal airtightness in buildings, it’s crucial to identify and address potential weak points where air leakages might occur. These weak points, often arising from various construction phases or oversight, can significantly compromise the energy efficiency of a structure. Our on-site experiences have illuminated some of the most recurrent areas of concern.

5.1 Gaps around Window Frames, Doors, and Floor Joists

The Issue: Improper sealing or alignment of windows and doors often leads to discernible gaps, while floor joists can sometimes be overlooked in terms of insulation and sealing.
The Solution: Utilising high-quality sealants, ensuring precise fittings, and opting for insulated frames can effectively mitigate these issues. Further, insulation between floor joists can restrict air flow and enhance thermal efficiency.

5.2 Hollow Sections in Suspended Floors or Walls

The Issue: These sections can act as conduits for unwanted airflow due to cavities created during construction or as a design feature.
The Solution: Proper insulation within these hollow sections or using solid construction techniques can reduce or eliminate such air pathways.

5.3 Cracks in Masonry or Gaps Behind Plasterboards

The Issue: Natural settling of buildings or subpar masonry can result in cracks. Similarly, improperly installed plasterboards can leave air pockets.
The Solution: Regular building inspections can help identify these issues early on. Filling cracks with appropriate sealants or mortar and ensuring flush plasterboard installations can address these concerns.

5.4 Areas Around Pipes, Vents, Heating Systems, and Electrical Fixtures

The Issue: These installations often require openings in walls, floors, or ceilings. If not sealed correctly, they can become significant sources of air leakages.
The Solution: Using gaskets, sealants, or specially designed collars around these installations can ensure a tight fit and minimise air infiltration.

5.5 The Imperative of Meticulous Inspection

Ensuring airtightness is not merely about addressing the obvious points of leakage but also about conducting thorough and regular inspections:

Proactive Identification: Regular inspections, especially post-construction and during maintenance phases, can spot potential problem areas before they escalate.
Leveraging Technology: Tools like thermal imaging cameras can visually pinpoint areas of air leakage, making the task of sealing and repair more targeted.
Skilled Professionals: Engaging professionals with expertise in building diagnostics can lead to more accurate identification of leakage points and suitable solutions.

In summary, while contemporary construction offers numerous advantages, it also brings its own set of challenges. By understanding and addressing common air leakage points, we can significantly improve the energy efficiency and comfort levels of a building. Meticulous inspection, combined with preventive and corrective measures, ensures that our structures stand the test of time and utility.

Image showing Airtightness Test at Red Brick House, North London, showing the blower door test being set up — ^{Airtightness Test at Red Brick House, North London, showing the blower door test being set up}

Chapter 6: The Airtightness Barrier: An Architect’s Tool

The airtightness barrier often likened to an invisible shield, plays a pivotal role in modern architectural design. Its essence lies in ensuring that a structure remains as impervious to unwanted air infiltration and exfiltration as possible, preserving energy efficiency and promoting a comfortable interior environment. But what is this barrier, and how can architects integrate it seamlessly into their designs?

6.1 Understanding the Airtightness Barrier

Definition: The airtightness barrier isn’t just a single layer or component. Instead, it’s a holistic system, encompassing a variety of materials and techniques, all working in unison to prevent unwanted airflow. This might include membranes, tapes, sealants, and gaskets.
Functionality: Beyond just preventing air leakage, this barrier also ensures the controlled exchange of air. This means that while uncontrolled air leakage is minimised, ventilation systems can operate more efficiently, ensuring good indoor air quality.

6.2 Integration at the Design Stage

Holistic Approach: Rather than being an afterthought, the airtightness barrier must be integrated right from the conceptual stage of design. This ensures that the barrier complements structural and aesthetic elements rather than hindering them.
Flexible Solutions: Depending on the building type, purpose, and location, the specifics of the barrier can vary. Thus, architects need to tailor the barrier to each project’s unique needs.

6.3 Key Considerations for Architects

Material Selection: Architects should opt for durable and resilient materials for the barrier, considering the local climate, potential exposure conditions, and desired lifespan of the structure.
Seamless Transitions: Where different materials or building components meet, there’s a heightened risk for air leakage. Architects should design in such a way that these transitions are meticulously sealed and guarded against potential breakages.
Incorporating Ventilation: While the objective is to minimise uncontrolled air leakage, architects must also plan for controlled ventilation, like Mechanical Ventilation Heat Recovery (MVHR). This ensures fresh air exchange without compromising the efficiency of the barrier.

6.4 Future Innovations and Adaptations

Technology-Driven Solutions: As building technology evolves, architects can leverage advanced tools and software to simulate and test the efficacy of their airtightness barrier designs.
Continuous Learning and Upgradation: The world of architecture is in perpetual evolution. By staying attuned to emerging best practices and novel materials, architects can continually refine their approach to airtightness.

In conclusion, the airtightness barrier is an indispensable tool in the architect’s arsenal. It not only upholds the energy efficiency and comfort of a building but also accentuates the importance of forward-thinking, sustainable design. By weaving this barrier seamlessly into the fabric of their designs, architects are able to create structures that stand as testimonies to both form and function.

Image of Visible smoke used during the Door Blower test to detect leakages in the building fabric — ^{Visible smoke used during the Blower Door test to detect leakages in the building fabric}

Chapter 7: Developing an Airtightness Strategy: From the Drawing Board to the Site

The art of crafting a building that stands against the onslaught of uncontrolled airflow is no mean feat. An airtight building is not just about integrating specific materials but encapsulating a vision that spans from initial sketches to the very last brick. The journey is intricate, demanding a blend of foresight, strategy, and concerted teamwork.

7.1 Setting Clear Performance Targets

Benchmarks and Metrics: Every successful airtightness strategy commences with well-defined targets. By stipulating specific air leakage rates or other measurable benchmarks, the project sets clear expectations from the outset.
Adherence to Regulations: While setting targets, it’s imperative to align with existing building regulations and guidelines, ensuring that the building not only meets but exceeds industry standards.

7.2 Leveraging Performance-based Specifications

Material and Component Selection: Using performance-based specifications means that materials and components are chosen based on their ability to meet the desired performance criteria, rather than just their inherent characteristics.
Continuous Assessment: Regular performance evaluations during construction ensure that the project remains on track and that any discrepancies can be addressed promptly.

7.3 Ensuring Stakeholder Alignment

Workshops and Training: It’s pivotal that everyone involved, from masons to electricians, is on the same page. Hosting workshops or training sessions can help familiarising teams with the airtightness strategy.
Regular Communication: Open lines of communication between teams can facilitate the identification and resolution of potential airtightness challenges. Frequent meetings, updates, and feedback sessions can prove beneficial.

7.4 The Role of the ‘Airtightness Champion’

Duties and Responsibilities: The Airtightness Champion is not just a title. This person is tasked with overseeing the entirety of the airtightness strategy, from monitoring material procurement to ensuring quality control on-site.
Bridging the Design-Construction Gap: One of the pivotal roles of the Airtightness Champion is to ensure a seamless transition of the airtightness vision from design to construction, eliminating ambiguities or misinterpretations.
Advocacy and Awareness: This champion also plays an educational role, advocating for best practices, introducing new techniques, and ensuring all members understand the importance of airtightness.

7.5 Iterative Refinement and Feedback

Post-Construction Analysis: Once a project is completed, a thorough analysis can provide insights into what worked and areas of improvement. This feedback can then inform future projects.
Incorporating Technological Tools: Tools such as blower door tests or thermal imaging can offer real-time data during construction, facilitating adjustments in the airtightness strategy as needed.

In summary, creating an airtight building is a symphony of precise strategy, unwavering focus, and harmonious teamwork. It’s about setting clear visions, arming oneself with the right tools, and ensuring every hand that touches the project does so with airtightness in mind. With such a holistic approach, the resulting structures not only stand firm against air leakages but also serve as benchmarks for others to emulate.

image of Blower Door Test being set up at our Red Brick House in Willesden, North West London to test airtightness — ^{Blower Door Test being set up at our Red Brick House in Willesden, North West London}

Chapter 8: Practical Steps to Achieving Airtightness

Airtightness is as much about tangible measures as it is about theory. Successful integration of airtightness in a building requires attention to detail, a deep understanding of materials, and rigorous processes. Here, we delve into some of the hands-on steps we’ve employed to translate our airtightness strategy into concrete outcomes.

8.1 The Imperative of Air Barriers

Characteristics of Ideal Barriers: The crux of airtightness lies in choosing barriers that are impermeable to airflow, continuous across junctions, and durable over time. Whether it’s a vapour barrier or a more rigid material, ensuring its continuity is essential to prevent leakages.
Positioning and Installation: Air barriers must be placed in areas where they won’t be compromised by subsequent building processes or later modifications.

8.2 Sealing Laps in Membranes

Material Selection: Specialised tapes and adhesives are imperative for ensuring the tightness of joins in air barrier membranes. Opting for high-quality materials that adhere well and remain effective over time is vital.
Technique: Correct lapping, typically overlapping the upper layer over the lower one, ensures that any water moving downwards doesn’t penetrate the barrier.

8.3 Window, Door, and Fixture Sealing

High-Quality Sealants: Using premium-grade sealants, which offer long-lasting protection against the elements, is paramount.
Attention to Detail: This involves not just the external perimeter but also areas like window and door sills, which can often be overlooked. Ensuring full perimeter sealing can drastically reduce air leakage.
Insulation: Beyond sealing, effective insulation of these openings, using products like expanding foam, can further enhance airtightness, but care must be taken when using expanding foam as studies have found that the foam can degrade over time creating air leakages.

8.4 Addressing Services in External Walls and Floors

Seal Service Penetrations: All service conduits, whether for electricity, water, or gas, must be meticulously sealed at the point they penetrate external barriers. This can be achieved using collars, grommets, or specific sealants.
Regular Inspection: Over time, seals can degrade or become compromised. Regular inspections can ensure any wear and tear is promptly addressed.

8.5 Airtight Light Fittings and Redundancy Measures

Lighting Considerations: Opting for airtight light fixtures ensures that the integrity of ceilings isn’t compromised. Where traditional fittings are used, additional sealing measures might be needed.
Unused Areas: Features like unused fireplaces can become significant sources of air leakage. Installing chimney balloons or draught-proofing measures can effectively block these off.

In conclusion, achieving airtightness is a meticulous process, requiring a blend of the right materials, expert techniques, and regular quality checks. By committing to these practical steps, we bring the theory of airtightness to life, crafting structures that are not only energy-efficient but also resilient against the elements.

Chapter 9: The Crucial Role of Testing in Airtightness

Achieving airtightness is not a matter of mere assumption or theory. It’s a tangible quality, measurable and quantifiable, and this is where testing comes into play. Comprehensive testing serves as a confirmation of our design and construction practices and provides invaluable insights into potential improvements.

9.1 The Essence of Air Testing

Objective Measurement: Airtightness tests offer a quantitative assessment, translating the efficacy of our strategies into measurable metrics. This allows us to assess if we have met or exceeded the set airtightness standards.
Timely Detection: By integrating testing at various stages of construction, from the initial phases to the final touches, we can swiftly pinpoint and rectify areas that aren’t meeting the desired standards.

9.2 Techniques and Tools: From Smoke Sticks to Pressure Tests

Smoke Sticks: A basic yet highly effective technique, smoke sticks or pencils emit visible smoke that gets drawn towards areas of air ingress. This not only visually demonstrates the leakage points but also offers an immediate way to gauge the severity of the issue.
Blower Door Test: This is a more comprehensive technique, involving the use of a powerful fan to depressurise the building. By measuring the rate at which air flows into the structure to equalise the pressure, this test provides an accurate measure of the building’s overall airtightness.
Thermal Imaging: Infrared cameras can detect differences in temperature caused by air leakages. This visual method is particularly useful in large structures or in conditions where other methods might be less effective.

9.3 Proactive Addressing of Issues

Immediate Rectifications: Once a leakage point is detected, immediate steps can be taken to address the issue. This might involve additional sealing, repairs, or even redesigning certain components.
Iterative Testing: After making necessary modifications, the area or the building can be re-tested to ensure that the remediation has been effective.

9.4 The Broader Impact of Testing

Ensuring Compliance: Regular testing ensures that our buildings are compliant with the latest regulatory standards, protecting stakeholders from potential legal implications and ensuring the building’s occupants reap the full benefits of an airtight structure.
Building Confidence: Regular testing instils confidence in both our team and our clients. It demonstrates our commitment to quality, precision, and energy efficiency.

It’s evident that testing is not just a regulatory necessity but an architect’s ally. It offers a clear pathway, turning the abstract concept of airtightness into a concrete achievement. With each test, we come closer to perfecting our understanding of the intricate dance between design, materials, and construction in creating airtight buildings.

Chapter 10: Airtightness Standards: An Overview

Navigating the realm of architectural design and construction without a thorough understanding of prevailing airtightness standards is akin to sailing without a compass. These standards, often instituted by reputed bodies and research organisations, form the foundation for modern sustainable building practices.

10.1 The Evolution of Airtightness Standards

Historical Context: The recognition of the importance of airtightness is not a recent phenomenon. Over the decades, as our understanding of energy efficiency grew, so did the push for more stringent standards. Initially focused on mere conservation, today’s standards strive for holistic sustainability.
Current Trends: As technology and construction methodologies advance, so do the benchmarks. Today, the push is not just for airtightness but also ensuring that buildings have effective ventilation, striking a balance between energy conservation and indoor air quality.

10.2 Key Organisations and Their Contributions

British Standards Institute (BSI): As the national standards body of the UK, the BSI plays a pivotal role in formulating airtightness standards. Their guidelines are comprehensive, covering aspects from material selection to construction techniques, and serve as a reference point for many professionals in the industry.
Building Research Establishment (BRE): BRE, with its extensive research and consultancy in the built environment, provides invaluable insights and recommendations. Their studies often inform the evolution of standards, ensuring they are rooted in empirical evidence and practical experience.

10.3 Interpreting the Standards: Beyond the Jargon

Quantitative Benchmarks: Most standards provide specific numerical values that buildings should adhere to. These might pertain to the permissible air leakage rates, insulation levels, or the efficacy of ventilation systems.
Qualitative Guidelines: Apart from numbers, standards often offer qualitative advice, covering best practices, potential pitfalls, and recommendations for various construction scenarios.
Case Studies and Examples: Many standards, especially those by research bodies like BRE, also provide real-world case studies. These examples offer a practical perspective, illustrating how the standards translate in real-world scenarios.

10.4 The Global Perspective

International Standards: While the UK has its unique standards, it’s crucial to be aware of international benchmarks, especially when working on projects with global stakeholders or in different countries. Organisations like the International Organisation for Standardisation (ISO) provide guidelines that often influence or align with national standards.
Adapting to Local Context: While standards provide a general framework, each building project has its unique context. It’s essential to adapt these guidelines considering local conditions, materials available, and specific project requirements.

In summary, while airtightness standards can initially seem overwhelming, they are invaluable tools in the architect’s arsenal. By staying updated, understanding the rationale behind these standards, and applying them judiciously, architects and builders can ensure that their creations are not just aesthetically pleasing but also environmentally responsible and sustainable.

Image showing Some popular airtightness membranes include: 01 Pro Clima Intello I 02 Ampatex / 03 Isover Vario / 04 Medite Smartply ProPassiv airtight OSB / 05 Blowerproof liquid airtight paint / 06 Airstop Diva Forte — ^{Some popular airtightness membranes include: 01 Pro Clima Intello I 02 Ampatex / 03 Isover Vario / 04 Medite Smartply ProPassiv airtight OSB / 05 Blowerproof liquid airtight paint / 06 Airstop Diva Forte. Image credit: Passivehouse Plus}

Conclusion: Airtightness – The Architectural Keystone of Tomorrow

In the vast expanse of architectural elements, airtightness, once perhaps seen as a mere footnote, has steadily grown in stature. The burgeoning focus on sustainability, climate change mitigation, and the inexorable drive for energy efficiency, has placed airtightness at the very heart of contemporary building design and construction.

The Holistic Impact of Airtightness
Airtightness isn’t an isolated discipline; it has a domino effect. Enhanced airtightness in buildings not only conserves energy but also elevates indoor air quality, reduces energy bills, and diminishes the carbon footprint of the structure. It’s a singular solution with multifaceted benefits.

Adapting to a Changing Climate
The global climate crisis mandates swift and effective responses. Buildings, as significant consumers of energy, play a colossal role in either exacerbating or alleviating this crisis. Airtightness is one of the primary solutions within our grasp that can help transform the energy profile of our structures, making them more resilient and less demanding on our planet’s finite resources.

The Cultural Shift in Architectural Design
Beyond the hard metrics of energy savings and carbon reduction, there’s a cultural evolution at play. Homeowners, builders, and stakeholders are increasingly educated about the virtues of airtight design. As this cultural shift continues, architects and designers are in a prime position to lead the narrative, ensuring that airtightness isn’t just a technical specification but a central ethos.

The Road Ahead
There will undoubtedly be challenges. New materials, evolving technologies, and ever-changing regulations will keep the architectural and construction industries on their toes. But with challenge comes opportunity. The commitment to airtightness represents an opportunity to reimagine the buildings of tomorrow, creating structures that are harmonious with their environment, efficient in their function, and exemplary in their design.

In the final analysis, airtightness is more than a technical requisite; it’s a testament to our collective responsibility. It’s about crafting buildings that don’t just stand as monuments to our creativity but as symbols of our commitment to a sustainable future. As we stand on the precipice of architectural evolution, addressing airtightness isn’t just a choice – it’s an imperative for the generations to come.

If you would like to talk through your project with the team, please do get in touch at mail@risedesignstudio.co.uk or give us a call on 020 3290 1003

RISE Design Studio Architects company reg no: 08129708 VAT no: GB158316403 © RISE Design Studio. Trading since 2011.

The Future of London’s Historic Houses: Revitalising the Old with EnerPHit Refurbishments

Posted on July 27, 2023 by Sean Ronnie Hill

Our journey in refurbishing London’s historic homes has led us to embrace the EnerPHit refurbishment strategy. This methodology guides us in revitalising older buildings to meet modern efficiency standards, and crucially, aligns with the government’s ‘2050 net-zero‘ carbon emissions target. In this article, we describe how we can upgrade the existing housing stock using EnerPHit methods.

Chapter 1: Understanding the Peculiarities of London’s Historical Housing Stock

London is adorned with a rich tapestry of architectural history – a city where centuries-old Victorian, Georgian, and Edwardian properties rub shoulders with sleek modern buildings. This interweaving of past and present not only enhances the city’s charm but also contributes to its distinct visual and community identity. However, these heritage buildings often underperform in terms of thermal efficiency and are not prepared to meet the challenges of our changing climate.

Queen's Park House in Queen's Park, NW London, which included upgrading the existing walls with internal wall insulation. — ^{Queen’s Park House in Queen’s Park, NW London, which included upgrading the existing walls with internal wall insulation.}

Chapter 2: Bridging the Past and Future: The Challenge of Energy Efficiency

To reduce our carbon footprint and limit global heating to 1.5 degrees, we must address the deficiencies in these older homes’ thermal design. Often, these buildings are about 3 times less thermally efficient than their contemporary counterparts that meet current building regulations standards. Therefore, it’s crucial to employ modern construction techniques that uphold the character of these historic properties while improving their energy performance.

Chapter 3: Retrofitting London’s Historic Homes with EnerPHit Standards

EnerPHit, a term combining ‘energy’ and the ‘Passive House’ (Passivhaus) concept, offers an effective strategy for overhauling these old structures. Like an insulated flask, an EnerPHit-compliant building retains the right temperature with minimal need for active cooling or heating. Achieving this requires a concerted approach involving well-insulated building envelopes, high-performing windows, efficient ventilation systems, airtight construction, and the elimination of thermal bridges.

Chapter 4: An Architect’s Guide to Implementing EnerPHit Principles

The transition to energy-efficient homes may seem daunting, especially when dealing with older properties. However, with thoughtful planning and a commitment to sustainable design, it’s possible to enhance energy performance while retaining the structure’s unique character. The crucial aspect here is understanding how the five fundamental EnerPHit requirements can be integrated into each project.

The five EnerPHit requirements are:

High levels of insulation — either internal or external, although internal needs more care in terms of moisture risk
High-performance triple-glazed windows and external doors
Careful consideration of window installation
An airtightness reading of 1.0
A Mechanical Ventilation with Heat Recovery (MVHR) system

Micro-generation of power, like Solar PVs, can be added to increase the low-energy nature of the home.

Chapter 5: EnerPHit Certification: A Holistic Approach to Refurbishment

EnerPHit certification offers a comprehensive framework for refurbishing existing buildings. It promotes a comprehensive understanding of the built environment, allowing architects to identify ‘easy wins’ for energy savings. The certification process can also be phased to accommodate complex refurbishment projects.

Chapter 6: The Importance of Precise Evaluation and Data Analysis

Before diving into design and construction, it’s essential to thoroughly understand the current state of the building. This understanding relies heavily on data, including quantitative analysis of condensation levels, and thermal imaging, as well as qualitative assessments of structural conditions and notable features. The data gathered will help architects identify suitable solutions to mitigate energy wastage and prevent further decay.

^{Ice Cream House in Hampstead, North London, has been designed using EnerPHit methods including high levels of insulation, high-performance glazing, airtightness, MVHR, ASHP and Solar PVs.}

Chapter 7: Case Study: The Ice Cream House Refurbishment

A practical example of an EnerPHit refurbishment project is our Ice Cream House located in Camden’s conservation areas. The homeowners sought to revamp the 1890s property to suit their contemporary lifestyle. Recognising the opportunity to add long-term environmental value, we applied EnerPHit standards in designing the extensions and internal modifications.

Chapter 8: Tying Old and New: The Role of Material Selection

The Ice Cream House refurbishment not only improved the energy performance but also harmonized old and new elements. The existing building envelope, initially a solid brick skin, was updated with low embodied carbon materials like internal insulation and clay plaster finishes. High-performance double-glazing windows with FSC timber insulated frames were installed for the sash windows, further boosting the house’s energy efficiency.

^{MVHR ducting at Herbert Paradise in Kensal Rise, NW London}

Chapter 9: MVHR and Renewable Energy Integration

To ensure superior indoor air quality, a mechanical ventilation heat recovery (MVHR) system was implemented across the entire property. The MVHR system expels stale air while retaining most of the heat, thereby enhancing energy efficiency. An air source heat pump (ASHP) was also added to satisfy residual energy demands post-renovation as well as Solar Photovoltaic Panels on the rear outrigger roof, helping to edge the property towards a ‘net zero’ state.

^{An 8 Panel 340W Solar PV System at Ice Cream House in Hampstead, North London}

Chapter 10: The Future of Historical Properties: Balancing Heritage and Sustainability

As we look to the future, retrofitting older properties with EnerPHit principles is no longer an option but a necessity. The challenge, however, lies in achieving a delicate balance between preserving the character and heritage of these buildings and introducing the essential elements of modern, energy-efficient design. Just as our predecessors strived for homes that reflected their time, we too must work towards creating homes that will serve the needs of future generations. To accomplish this, architects must commit to sustainable refurbishment practices.

In conclusion, the road to ‘net-zero 2050’ requires a radical rethink of our approach to the existing housing stock. As architects, we have a unique role in shaping this transformation. It’s time we step up and embrace the change, preserving the past while preparing for the future.

Aerial view of Queen's Park, North West London, with the city centre in the background — ^{Aerial view of Queen’s Park, North West London, with the city centre in the background}

Frequently Asked Questions

1. What does ‘net-zero 2050’ mean?

‘Net-zero 2050’ is a target set by many governments, including the UK, to achieve net-zero carbon emissions by the year 2050. This means that by 2050, the amount of greenhouse gases produced will be balanced by the amount removed from the atmosphere, effectively reducing our impact on climate change.

2. What is the EnerPHit refurbishment strategy?

EnerPHit is a strategy for retrofitting existing buildings to drastically reduce their overall energy demand. This is achieved by implementing standards used in Passive House (Passivhaus) construction, which include a well-insulated building envelope, strategic window placement, efficient heat recovery and ventilation systems, an airtight envelope, and avoidance of thermal bridges.

3. What is the Passive House concept?

The Passive House (Passivhaus) concept refers to a rigorous, voluntary standard for energy efficiency in a building. This reduces its ecological footprint, resulting in ultra-low-energy buildings that require little energy for heating or cooling. EnerPHit is the term used when these standards are applied to existing buildings.

4. How can EnerPHit refurbishment address thermal efficiency in older homes?

EnerPHit refurbishment can drastically improve thermal efficiency in older homes by addressing issues such as airtightness, insulation, and ventilation. By implementing EnerPHit principles, these homes can retain warmth during colder months and stay cool during warmer ones, significantly reducing their energy demand and carbon emissions.

5. How is EnerPHit certification achieved?

EnerPHit certification involves a thorough and holistic evaluation of the building. This includes measuring functions like primary energy demand and assessing the performance of components such as windows, doors, and ventilation systems. It also takes into account the building’s existing fabric and allows for phased works to be completed over time.

6. What is the role of data in EnerPHit refurbishments?

Data plays a vital role in understanding a building’s current condition before refurbishments. It allows for a quantitative analysis of aspects like condensation levels, and thermal imaging, as well as qualitative assessments of structural conditions and unique features. This information guides architects towards proven solutions to mitigate energy wastage and further decay.

7. How do materials selection impact EnerPHit refurbishments?

Materials play a critical role in the EnerPHit refurbishment process. The choice of materials can greatly influence the building’s thermal performance, airtightness, and overall sustainability. Using low embodied carbon materials, such as internal wood-fibre insulation, clay plaster and timber structure (as opposed to steel), can help reduce a building’s overall carbon footprint.

8. How does a Mechanical Ventilation Heat Recovery (MVHR) system function?

An MVHR system extracts stale air from a building while retaining most of the heat. The heat exchanger in the system transfers internal heat from outgoing air to incoming fresh external air. This helps maintain indoor air quality, provides a constant fresh air supply, and increases energy efficiency.

9. What is an Air Source Heat Pump (ASHP), and how does it contribute to energy efficiency?

An ASHP is a device that absorbs heat from the outside air and uses it to heat water for space heating. This process continues to work even when the external temperature is as low as -15° C. An ASHP can significantly contribute to a building’s energy efficiency by meeting the residual energy demands after a full renovation.

10. How does the EnerPHit refurbishment strategy balance heritage and sustainability in older buildings?

EnerPHit refurbishment focuses on upgrading a building’s energy performance while preserving its unique characteristics. This involves sensitive upgrades that maintain the building’s aesthetic and historical value, like replacing old components with high-performing replicas, while improving insulation, airtightness, and ventilation for increased energy efficiency. This delicate balance between heritage and sustainability ensures that the historical integrity of the property is maintained while it meets modern-day energy requirements.

If you would like to talk through your project with the team, please do get in touch at mail@risedesignstudio.co.uk or give us a call on 020 3290 1003

RISE Design Studio Architects company reg no: 08129708 VAT no: GB158316403 © RISE Design Studio. Trading since 2011.

What is EnerPHit? Is it right for my home retrofit project?

Posted on June 2, 2023 by Sean Ronnie Hill

EnerPHit aims to achieve similar levels of energy efficiency as Passivhaus for retrofitted buildings. In this guide, I will provide you with a comprehensive overview of EnerPHit, its requirements, the benefits it offers, and the considerations you need to keep in mind if you are planning a retrofit project.

EnerPHit vs. Passivhaus

While Passivhaus standards are primarily applied to new builds, EnerPHit focuses on retrofitting existing properties. Retrofit refers to a form of renovation aimed at significantly reducing energy consumption and improving the thermal performance and comfort of a home. Unlike Passivhaus, which can start from a blank canvas, retrofitting involves working with existing buildings where many elements like geometry, orientation, and structural approach are already predetermined. Additionally, retrofit projects may have thermal bridges (or cold bridges) that are challenging to eliminate completely.

The EnerPHit standard acknowledges these challenges and sets slightly lower performance requirements compared to Passivhaus, considering the limitations of retrofitting existing buildings. To meet the EnerPHit standards, a space heating and cooling demand of 25 kWh/m2/year is required (compared to the Passivhaus standard of 15 kWh/m2/year). Airtightness performance should achieve 1.0 air changes per hour (compared to the Building Regulations for new homes, which require between 5 and 15 air changes per hour). While achieving these standards may use more energy than Passivhaus, it still represents a significant improvement over most existing homes and even new builds.

Douglas House, Kensal Rise, North West London. Douglas House includes MVHR, high levels of insulation and airtightness — ^{Douglas House, Kensal Rise, North West London. Douglas House includes MVHR, high levels of insulation and Airtightness and Solar PVs}

Guidelines and Design Considerations

EnerPHit provides a benchmark for renovators to work towards. Similar to Passivhaus, the Passivhaus Planning Package (PHPP) design tool is used when designing an EnerPHit scheme. This tool helps deliver more efficient buildings by considering factors like orientation and geometry at an early design stage. The PHPP enables informed decision-making regarding retrofit measures, cost implications, and energy considerations.

It’s important to note that retrofitting is not an easy task, and achieving the EnerPHit standard requires careful planning and execution. The thermal and airtightness strategies are likely to be more complex and challenging on site compared to new builds. Balancing the pros and cons of internal or external insulation is a critical consideration, as well as addressing potential moisture issues that may arise from changing the building fabric. Undertaking an EnerPHit retrofit demands a skilled and knowledgeable design team that can navigate these complexities.

Retrofit Measures and Certification Process

When carrying out an EnerPHit retrofit, several measures are required to meet the standard. These include:

High levels of insulation, either internal or external (with internal insulation requiring more attention to moisture risk)
High-performance triple-glazed windows and external doors
Careful window installation
Achieving an airtightness reading of 1.0, and
Implementing a Mechanical Ventilation with Heat Recovery (MVHR) system.

To receive EnerPHit certification, the process is similar to working towards Passivhaus certification. The project must be designed using the PHPP and certified by an accredited Passivhaus certifier. While the products used in the retrofit do not need to be Passivhaus certified, having certified products, especially for MVHR equipment, can be beneficial.

To make EnerPHit retrofits more accessible, the Passivhaus Institute has introduced the EnerPHit Retrofit Plan, a step-by-step certification process that allows payments for certification to be made in stages. This helps with funding for retrofit projects and provides a structured approach to achieving certification.

^{Herbert Paradise, Kensal Rise, North West London. Includes MVHR, ASHP, Airtightness, Solar PV and high levels of insulation}

Cost Considerations

The cost of an EnerPHit retrofit can vary depending on the complexity of the existing building. As a general guideline, budgeting around £800-£1,000 per square meter for deep retrofit/EnerPHit, excluding VAT, is advisable. When considering specific components or systems, expect to pay around £10,000 for an MVHR unit installed in an average-sized house and approximately £400-£600 per square meter for windows and doors. However, the major costs lie in labor, as the installation of insulation and airtightness measures is time-consuming and requires meticulous attention to detail.

Insulation and Retrofit Challenges

One of the significant challenges faced by retrofitters is determining the optimal placement of insulation to improve the energy efficiency of existing houses. Regardless of where the insulation is placed, it is likely to create some issues. Internal wall insulation, for example, raises concerns about condensation and mold growth. When insulation is added to the inside of a wall, it can make the wall colder and disrupt the balance that previously allowed moisture to evaporate. This can lead to trapped moisture within the new wall assembly.

The Society for the Protection of Ancient Buildings (SPAB) has highlighted the issue of interstitial condensation and conducted research to better understand when and where it may occur. While specific recommendations may vary, the general advice is to avoid internal wall insulation in very exposed locations with porous external surfaces, as it can interfere with moisture management. This advice applies to buildings of any era, not just ancient ones.

^{Douglas House, Kensal Rise, North West London. Douglas House includes MVHR, high levels of insulation and Airtightness and Solar PVs}

Is EnerPHit Right for Your Home?

Considering an EnerPHit retrofit makes the most sense when you are already planning renovation or remodeling work on your house. If you are contemplating changes to your home to improve energy efficiency, EnerPHit offers a compelling opportunity. For instance, when replacing the roof or windows, it becomes easier to justify investing in high-performance materials that align with the EnerPHit standards.

While an extension project may not be the ideal time for a retrofit, it provides an excellent opportunity to create a long-term whole house plan that integrates the extension seamlessly and ensures compatibility with future retrofitting efforts. Planning for an EnerPHit retrofit from the beginning can help you achieve high levels of comfort and thermal performance in your home.

^{Light House, Clapham, South London. Light House includes MVHR, high levels of insulation and Airtightness and Solar PVs}

Conclusion

EnerPHit represents the pinnacle of energy-efficient retrofitting, aiming to bring existing properties to levels of energy efficiency comparable to Passivhaus standards. While retrofitting poses unique challenges compared to new builds, the EnerPHit standard provides guidelines and benchmarks for achieving exceptional performance. With careful planning, skilled design teams, and a comprehensive understanding of the complexities involved, EnerPHit retrofit projects can transform existing properties into low energy and low embodied carbon homes.

By adhering to the principles of EnerPHit and working towards certification, you ensure rigorous quality assurance, airtightness performance, and adherence to the design objectives. While EnerPHit retrofit costs can vary depending on the complexity of the project and project location, the long-term benefits of improved energy efficiency, comfort, and reduced carbon emissions make it a worthwhile investment for homeowners looking to create sustainable living spaces.

So, if you’re considering renovating your home with the goal of achieving high levels of comfort and thermal performance, now is the time to plan for an EnerPHit retrofit. Embrace the challenge, work with knowledgeable professionals, and unlock the potential of your existing property to become an energy-efficient haven that aligns with your sustainability goals.

If you would like to talk through your project with the team, please do get in touch at mail@risedesignstudio.co.uk or give us a call on 020 3290 1003

RISE Design Studio Architects company reg no: 08129708 VAT no: GB158316403 © RISE Design Studio. Trading since 2011.

Reimagining Architecture for a Sustainable Future: An Architect’s Perspective on the RIBA 2030 Climate Challenge

Posted on May 19, 2023 by Sean Ronnie Hill

With the climate crisis at the forefront of global challenges, the Royal Institute of British Architects (RIBA) has set forth an important initiative, the 2030 Climate Challenge. Below we delve into this and share the nuances of the initiative and its implications for the architectural world.

Image of a contemporary rear extension in Queen's Park, NW London — ^{Queen’s Park House in NW London by RISE Design Studio}

Chapter 1: RIBA’s 2030 Climate Challenge: Paving the Path for Sustainable Architecture

In the ever-evolving landscape of architectural design and construction, the need for sustainability has become paramount. As the world grapples with the pressing issue of climate change, architects are at the forefront of a transformative movement towards environmentally responsible practices. Among the vanguard of this movement is the Royal Institute of British Architects (RIBA), which has set forth a visionary initiative known as the “2030 Climate Challenge”. This initiative embodies a commitment to fostering sustainable architects who will shape the future of the built environment in the United Kingdom.

RIBA’s Vision for Sustainability

At the heart of the 2030 Climate Challenge are RIBA’s ambitious objectives. This challenge serves as a call to action for RIBA Chartered Practices, urging them to embrace and uphold specific performance targets. These targets encompass critical aspects of sustainability, including energy use, water consumption, and embodied carbon. By delineating these voluntary benchmarks, RIBA aspires to guide the architectural community towards a collective goal: achieving a net-zero carbon future for the entire UK building stock by the year 2050.

Energy Efficiency: A Pillar of Sustainable Design

One of the primary pillars of RIBA’s 2030 Climate Challenge is energy efficiency. Sustainable architects, under the guidance of RIBA, are encouraged to develop innovative design solutions that minimise energy consumption. This involves harnessing natural light, implementing passive heating and cooling systems, and incorporating renewable energy sources wherever feasible. By setting specific targets for energy efficiency, RIBA seeks to reduce the carbon footprint of new and existing buildings, effectively curbing the sector’s contribution to climate change.

Water Conservation: A Precious Resource Preserved

Another vital facet of sustainable architecture lies in water conservation. The challenge urges architects to adopt practices that mitigate water wastage, both in the construction and operational phases of a building’s lifecycle. Sustainable architects employ techniques such as rainwater harvesting, greywater recycling, and low-flow fixtures to achieve these goals. RIBA recognises that safeguarding this precious resource is paramount in the fight against climate change and environmental degradation.

Embodied Carbon: Building Responsibly for the Future

A central tenet of RIBA’s 2030 Climate Challenge is the concept of embodied carbon. Sustainable architects are tasked with minimising the carbon emissions associated with a building’s construction materials and processes. This involves carefully selecting sustainable materials, promoting circular economy principles, and reducing waste during construction. By focusing on embodied carbon, architects can contribute significantly to the long-term sustainability of the built environment, aligning their practices with RIBA’s vision of a net-zero carbon future.

The Role of Sustainable Architects

Sustainable architects are the vanguards of change in the architectural profession. They play a pivotal role in shaping a future where buildings are not merely functional structures but guardians of the environment. Through their dedication to RIBA’s 2030 Climate Challenge, sustainable architects demonstrate a commitment to creating spaces that are ecologically responsible, energy-efficient, and climate-friendly.

Chapter 1 Conclusion

RIBA’s 2030 Climate Challenge sets a clear trajectory for the architectural community in the UK. It calls upon sustainable architects to embrace a new era of design and construction, where sustainability is not an option but an imperative. By committing to specific targets related to energy use, water conservation, and embodied carbon, architects are aligning themselves with a vision of a greener, more sustainable future. As they navigate the complex terrain of climate change and environmental preservation, these architects are poised to be the driving force behind the transformation of the UK building stock into a net-zero carbon exemplar by 2050.

^{RIBA 2030 Climate Challenge – The RIBA has developed voluntary performance targets for operational energy use, water use and embodied carbon.}

Chapter 2: The Urgency of Action: Sustainable Architects Leading the Way

In recent years, the world has witnessed the sobering reality of climate change. The past decade stands as a stark reminder, with record-breaking temperatures and extreme weather events becoming increasingly commonplace. Against this backdrop, the imperative of immediate response looms large. While the UK Government has set the ambitious target of achieving net-zero greenhouse gas emissions by 2050, the architectural industry must also rise to the occasion. Sustainable architects, in particular, find themselves at the forefront of this battle, equipped with strategies and solutions that can help mitigate the climate crisis.

The Climate Emergency: A Decade of Warnings

The past decade’s record-breaking warmth is not a mere statistical anomaly but a chilling indication of the Earth’s changing climate. Rising global temperatures, melting ice caps, and more frequent and severe weather events all serve as dire warnings of a planet in peril. The urgency of addressing climate change has never been more pronounced. It is a collective responsibility, and the architectural profession has a vital role to play in shaping a sustainable future.

Government Mandate and Industry Commitment

In response to the unfolding climate crisis, the UK Government has set a clear mandate: achieve net-zero greenhouse gas emissions by 2050. This commitment represents a monumental step towards a more sustainable future. However, the responsibility doesn’t rest solely on the shoulders of policymakers. The architectural industry must also take proactive measures to align itself with this ambitious goal. Sustainable architects, in particular, are well-positioned to lead this charge.

Net Zero Whole Life Carbon: A Paradigm Shift

Sustainable architects recognise that achieving net-zero carbon emissions is not merely about the operational phase of buildings but extends to their entire life cycle. This paradigm shift in thinking calls for a holistic approach to design and construction. Architects must consider the carbon footprint of materials, construction processes, and the eventual operation of a building. By prioritising net zero whole-life carbon, sustainable architects are redefining the way buildings are conceived, constructed, and maintained.

Emphasising Energy Demand Reduction

One of the most effective strategies for addressing the climate crisis is reducing energy demand. Sustainable architects are pioneers in this regard, employing innovative design principles and technologies to create buildings that are highly energy-efficient. From passive solar design and enhanced insulation to intelligent lighting and HVAC systems, architects are revolutionising the way buildings consume energy. By minimising energy demand, they not only reduce carbon emissions but also promote long-term cost savings for building owners and occupants.

Sustainable Architects: The Vanguard of Change

Sustainable architects are the torchbearers of a new era in the architectural profession. They embody the spirit of innovation and responsibility, harnessing their expertise to craft sustainable, resilient, and environmentally conscious designs. These architects understand that every building they design is a legacy, and they are committed to leaving a positive mark on the planet.

Chapter 2 Conclusion

As the world grapples with the consequences of a warming planet, the architectural industry finds itself standing at a pivotal crossroads. The urgency of the climate crisis demands immediate action, and sustainable architects are ready to lead the way. With a focus on net zero whole life carbon and energy demand reduction, they are reshaping the built environment for a more sustainable future. While the UK Government’s commitment to net-zero emissions by 2050 is a critical milestone, it is the collective efforts of architects and other industry stakeholders that will drive real change. In the hands of sustainable architects, the imperative of immediate response becomes a beacon of hope for a planet in need of healing.

Image of the front elevation of Douglas House in Kensal Rise, NW London, was designed to EnerPHit standards including additional insulation, high performance glazing, MVHR, Airtightness and Solar PVs. — ^{Douglas House in Kensal Rise, NW London, was designed to EnerPHit standards including additional insulation, high performance glazing, MVHR, Airtightness and Solar PVs.}

Chapter 3: The Evolution of the Challenge: Refined Goals for 2021

In its relentless pursuit of a sustainable future, the Royal Institute of British Architects (RIBA) has consistently adapted and refined its approach to the 2030 Climate Challenge. Since its inauguration in 2019, this initiative has undergone a significant transformation, ushering in Version 2 in 2021. This evolution not only demonstrates RIBA’s commitment to addressing the climate crisis but also reflects the dynamic nature of the architectural profession’s response to the challenge. Sustainable architects have been key contributors to this process, shaping and embracing the refined goals set forth in this updated version.

The Ongoing Climate Crisis: A Call for Adaptation

The climate crisis continues to escalate, making it imperative for organisations like RIBA to adapt and strengthen their initiatives. Record-breaking heatwaves, catastrophic wildfires, and devastating storms serve as constant reminders of the urgency of the situation. Sustainable architects have been at the forefront, advocating for more ambitious goals and practical strategies to combat climate change.

Version 2: An Aligned and Inclusive Approach

Version 2 (2021) of the 2030 Climate Challenge represents a significant step forward in aligning RIBA’s objectives with broader industry bodies. Recognising that a collaborative approach is essential, RIBA has worked closely with other stakeholders, including architectural associations, environmental organisations, and government bodies, to create a unified front against climate change. This alignment ensures that the goals set forth in the challenge resonate with the wider industry, fostering greater adoption and impact.

Incorporating the Latest Guidance

Sustainable architects understand that staying current with the latest industry standards and guidance is paramount to achieving meaningful change. Version 2 (2021) of the challenge reflects this ethos by incorporating the most up-to-date jointly authored guidance. This ensures that architects have access to the best practices and cutting-edge knowledge needed to design and construct environmentally responsible buildings.

Immediate Action Over Perfection

The updated challenge underscores a crucial philosophy: the necessity of immediate action, even if perfection isn’t yet achievable. Sustainable architects recognise that the climate crisis demands urgent responses and that waiting for the perfect solution is a luxury we can’t afford. Instead, they focus on incremental improvements, continuously refining their approaches, and learning from each project to make sustainable design more attainable and effective.

The Role of Sustainable Architects in Version 2

Sustainable architects are instrumental in driving Version 2 (2021) of the 2030 Climate Challenge. Their expertise in sustainable design, commitment to innovation, and dedication to environmental stewardship make them key contributors to the challenge’s evolution. They advocate for more ambitious targets, influence industry standards, and serve as beacons of inspiration for their peers. Their work not only transforms individual projects but also contributes to a broader shift towards a more sustainable built environment.

Chapter 3 Conclusion

As the world grapples with the escalating climate crisis, RIBA’s 2030 Climate Challenge continues to evolve, adapting to the changing landscape of sustainability. Version 2 (2021) represents a collaborative, inclusive, and action-oriented approach that resonates with the architectural community and industry stakeholders alike. Sustainable architects, with their unwavering commitment to the environment, play a pivotal role in shaping and embracing these refined goals. They understand that perfection may remain elusive, but immediate action is imperative. In this evolving challenge, sustainable architects stand as champions of progress, driving the architectural profession towards a more sustainable and resilient future.

Aerial view of the Lexi Cinema & Hub in Kensal Rise, NW London — ^{The Lexi Cinema & Hub in Kensal Rise, NW London, following Passivhaus design principles including super-insulated outer skin, airtightness, MVHR. It also includes an Air to Air Source Heat Pump, making it the first cinema in the UK to control the air temperature of the auditorium this way}

Chapter 4: Navigating the Ambitious Goals of RIBA’s 2030 Climate Challenge

The audacity of RIBA’s 2030 Climate Challenge is matched only by its feasibility. It is a call to action that beckons architects and the wider industry to make substantial and tangible contributions to the fight against climate change. The challenge sets out clear and ambitious targets, each meticulously designed to drive sustainability forward. Sustainable architects, with their innovative thinking and unwavering commitment to environmental stewardship, are pivotal in realising these objectives.

1. Reducing Operational Energy Demand by 60%

The first target of the challenge centres on the reduction of operational energy demand. Sustainable architects understand that buildings are responsible for a significant portion of global energy consumption and carbon emissions. To meet this ambitious goal, architects employ a range of strategies. These include harnessing renewable energy sources, enhancing insulation and airtightness, and integrating smart technologies for efficient energy management. Sustainable architects are adept at optimising building designs to significantly slash energy demand while maintaining comfort and functionality.

2. Decreasing Embodied Carbon by 40%

Embodied carbon, which accounts for emissions associated with a building’s construction materials and processes, is a critical aspect of sustainable design. Sustainable architects are well-versed in selecting low-carbon materials, promoting recycling and reuse, and reducing waste during construction. They also consider the carbon footprint of transportation and manufacturing processes. Through meticulous planning and innovative solutions, sustainable architects aim to achieve a 40% reduction in embodied carbon, contributing to a more sustainable built environment.

3. Reducing Potable Water Use by 40%

Water is a precious resource, and sustainable architects are keenly aware of the need to conserve it. The challenge’s target to reduce potable water use by 40% calls for the adoption of water-efficient fixtures, rainwater harvesting systems, and greywater recycling. Sustainable architects integrate these solutions seamlessly into building designs, reducing the strain on water resources while promoting responsible water management practices.

4. Meeting Core Health and Wellbeing Metrics

Beyond environmental sustainability, the challenge recognises the importance of human well-being in architectural design. Sustainable architects champion this cause by prioritising health and well-being metrics in their projects. They design spaces that promote natural light, good air quality, and access to green spaces. Moreover, they create environments that foster mental and physical health, enhancing the overall quality of life for building occupants.

Sustainable Architects: The Catalysts of Change

Sustainable architects are not merely tasked with meeting these challenging targets; they are the catalysts of change within the architectural profession. Their holistic approach to design integrates sustainability into every facet of the built environment. They push boundaries, challenge conventions, and demonstrate that ambitious sustainability goals are not only feasible but also economically and environmentally advantageous.

Chapter 4 Conclusion

RIBA’s 2030 Climate Challenge presents a bold vision for the future of architecture, one in which sustainability is at the core of every design and construction project. The granular targets set forth in this challenge may seem ambitious, but they are well within reach, thanks to the dedication and expertise of sustainable architects. These architects, with their commitment to reducing operational energy demand, decreasing embodied carbon, conserving water, and prioritising health and wellbeing, are reshaping the built environment for the better. As they navigate the complexities of sustainable design, they inspire and lead the way towards a more sustainable, resilient, and harmonious future for all.

^{Herbert Paradise in Kensal Rise, NW London, our low energy home designed following EnerPHit principles of design}

Chapter 5: Beyond Just Numbers: RIBA’s Advocacy for Holistic Design

In the journey towards a sustainable future, RIBA’s 2030 Climate Challenge stands as a pivotal beacon, guiding the architectural community towards a net-zero carbon future. Yet, it is essential to recognise that this challenge is about more than just achieving numerical targets; it represents a profound transformation in architectural design thought. Sustainable architects are not only striving to meet specific goals but also embracing outcome-based design methodologies that transcend mere numbers. This holistic approach is a fundamental paradigm shift, where every architectural project, regardless of external constraints, aspires to align itself with the 2030 targets from the outset.

Reimagining Architectural Design Thought

The traditional approach to architectural design often revolved around aesthetics, functionality, and immediate project constraints. However, the 2030 Climate Challenge challenges architects to reimagine their thought processes. Sustainable architects understand that design decisions made at the project’s inception can have a lasting impact on its environmental performance. They advocate for a broader perspective that encompasses not only the physical aspects of a building but also its long-term ecological footprint.

Outcome-Based Design: The New Imperative

The essence of outcome-based design is to prioritise the final result over the initial constraints. Sustainable architects are adept at envisioning the end goal – a sustainable, energy-efficient, and carbon-neutral building – and then working backwards to achieve it. This approach compels architects to think holistically, considering not only energy efficiency but also embodied carbon, water use, and the overall environmental and social impact of their designs.

Immediate Alignment with 2030 Targets

One of the most significant aspects of this holistic design approach is the insistence on immediate alignment with the 2030 targets. Sustainable architects recognise that waiting until the later stages of a project to consider sustainability can be too late. Instead, they advocate for incorporating sustainability into the project’s DNA from the very beginning. This proactive stance ensures that sustainability is not an afterthought but an integral part of the design process.

Overcoming External Hindrances

While the 2030 Climate Challenge may seem ambitious, sustainable architects view it as a non-negotiable imperative. They understand that external constraints, such as budget limitations or regulatory hurdles, should not be used as excuses to postpone sustainability goals. Instead, they see these challenges as opportunities for creativity and innovation. Sustainable architects work tirelessly to find solutions that make sustainable design not only achievable but also cost-effective and compliant with regulations.

Sustainable Architects: Pioneers of Holistic Design

Sustainable architects are the pioneers of this new era of architectural design. They are the architects of the future, forging a path towards a more sustainable and resilient built environment. Their commitment to outcome-based design methodologies transcends the limitations of traditional practices. They envision a world where every building, regardless of its size or purpose, is a testament to sustainability and environmental responsibility.

Chapter 5 Conclusion

RIBA’s 2030 Climate Challenge is not just a set of numerical targets; it represents a profound shift in architectural design thought. Sustainable architects champion this transformation, advocating for outcome-based design methodologies that prioritise sustainability from the project’s inception. Their commitment to immediate alignment with the 2030 targets and their ability to overcome external hindrances make them the vanguard of change within the architectural profession. As they continue to push the boundaries of design, sustainable architects are reshaping the way we conceive, construct, and inhabit our built environment, leaving a lasting legacy of sustainability for generations to come.

an aerial view of Ice Cream House in Hampstead — ^{Ice Cream House in Hampstead, N London, designed following EnerPHit principles of sustainable design}

Chapter 6: The Power of Data: Monitoring and Reporting in the 2030 Climate Challenge

In the quest for a more sustainable built environment, RIBA’s 2030 Climate Challenge harnesses a potent tool – data. This transformative initiative recognises that the collection and analysis of data are paramount in the pursuit of sustainability goals. Sustainable architects, as the driving force behind this movement, understand the pivotal role of data in monitoring and reporting on building performance. Through the submission of anonymised project data, they contribute to a collective endeavour that not only tracks progress but also identifies opportunities for improvement.

The Cornerstone of the 2030 Climate Challenge

Data is the cornerstone upon which the 2030 Climate Challenge is built. Participating firms are tasked with submitting comprehensive data related to their projects. This data encompasses various aspects, from energy consumption and water use to embodied carbon and overall building performance. By compiling this information, the challenge creates a comprehensive dataset that serves as a barometer for sustainability within the architectural community.

The Power of Anonymised Data

The significance of anonymised data cannot be overstated. Sustainable architects recognise the need to protect the confidentiality of individual projects while still leveraging the collective insights that data can provide. Anonymisation ensures that sensitive project details remain confidential, allowing firms to share their experiences and performance without compromising their proprietary information.

Understanding Building Performance Trends

Data is a powerful lens through which to examine building performance trends. Sustainable architects use this data to gain valuable insights into how design choices, construction methods, and operational practices impact a building’s environmental footprint. By identifying patterns and trends, architects can refine their approaches, making informed decisions that drive sustainability forward.

Identifying Areas of Improvement

The analysis of data goes beyond merely assessing success; it also highlights areas where improvement is needed. Sustainable architects view data as a diagnostic tool that helps them pinpoint weaknesses in their designs or practices. By identifying these areas of improvement, architects can iterate and refine their processes, driving continuous progress towards the 2030 targets.

Sustainable Architects: Data-Driven Decision Makers

Sustainable architects are adept at making data-driven decisions. They use the insights derived from the 2030 Climate Challenge data to inform their design choices, select materials with lower embodied carbon, and implement energy-efficient technologies. This data-centric approach empowers architects to create buildings that not only meet sustainability targets but also exceed them.

Chapter 6 Conclusion

In the 2030 Climate Challenge, data emerges as a formidable ally in the pursuit of sustainability. Sustainable architects, as the custodians of this data, understand its transformative potential. Through the submission of anonymised project data, they contribute to a collective effort that monitors progress, identifies trends, and pinpoints areas of improvement. Data is not merely a tool for reporting; it is a catalyst for change. It empowers architects to make informed, data-driven decisions that lead to a more sustainable and resilient built environment. As the architectural profession continues to evolve, sustainable architects stand as champions of data-driven sustainability, driving positive change for the benefit of future generations.

A photo of Bethany and Imran at Herbert Paradise discussing the ducting routes of the MVHR system — ^{Bethany and Imran at Herbert Paradise during construction discussing the ducting routes of the MVHR system}

Chapter 7: The Blueprint for Success: The 2030 Climate Challenge Checklist

In the pursuit of sustainability, the 2030 Climate Challenge offers a well-defined blueprint for success. This comprehensive checklist serves as a guiding light for Chartered Practices, providing a clear roadmap to navigate the complex terrain of sustainable design and construction. It encompasses a multitude of facets, from striving to meet reduced operational energy and embodied carbon targets to focusing on water efficiency and indoor health. Sustainable architects, armed with this invaluable tool, are equipped to chart a course towards a more sustainable, resilient, and environmentally responsible built environment.

Setting the Foundation: Reduced Operational Energy

Reducing operational energy demand is a fundamental goal in the 2030 Climate Challenge checklist. Sustainable architects understand that this involves a holistic approach to design, encompassing building orientation, insulation, efficient HVAC systems, and the integration of renewable energy sources. They use this checklist as a compass to ensure that their designs prioritise energy efficiency from the outset.

Minimising Environmental Impact: Embodied Carbon Targets

Embodied carbon is another critical aspect of the checklist. Sustainable architects are adept at selecting low-carbon materials, considering their life cycle impacts, and promoting the use of sustainable and recycled resources. By aiming to meet embodied carbon targets, architects minimise the environmental footprint of their projects, contributing to a more sustainable built environment.

Conserving a Precious Resource: Water Efficiency

Water efficiency is an integral part of the checklist. Sustainable architects recognise that water is a finite resource and that its responsible use is paramount. They employ strategies such as rainwater harvesting, greywater recycling, and the specification of water-efficient fixtures to meet water efficiency targets. This not only reduces the strain on water resources but also lowers operational costs for building owners.

Prioritising Human Wellbeing: Indoor Health Metrics

The checklist extends beyond environmental concerns to focus on the health and well-being of building occupants. Sustainable architects are champions of indoor health metrics, which encompass factors like air quality, natural lighting, and access to green spaces. They design spaces that promote physical and mental health, ensuring that occupants thrive in a supportive and nurturing environment.

Sustainable Architects: Navigators of Sustainability

Sustainable architects are the navigators of sustainability, using the 2030 Climate Challenge checklist as their compass. They understand that achieving these targets requires a holistic approach to design and construction. They leverage their expertise to ensure that every project aligns with the checklist’s objectives, transforming buildings into beacons of sustainability and environmental responsibility.

Chapter 7 Conclusion

The 2030 Climate Challenge checklist is more than just a list of targets; it is a blueprint for success in the pursuit of sustainability. Sustainable architects view this checklist as an invaluable tool that guides their decision-making processes, from design conception to project completion. By setting their sights on reduced operational energy, embodied carbon targets, water efficiency, and indoor health metrics, architects are not only meeting the challenge but also exceeding it. As they continue to evolve the architectural profession, sustainable architects are reshaping the built environment for a more sustainable, resilient, and harmonious future for all.

image of Solar panels on the rear outrigger roof at our Ice Cream House in Hampstead, N London — ^{Solar panels on the rear outrigger roof at our Ice Cream House in Hampstead, N London}

Chapter 8: Emphasising Existing Infrastructure: Retrofitting as a Sustainable Strategy

In the pursuit of sustainability, the architectural world is undergoing a paradigm shift. While new constructions have traditionally dominated the scene, there is a growing emphasis on retaining, reusing, and repurposing existing buildings. This transformative approach places retrofitting at the forefront of sustainable architectural strategies. Sustainable architects understand that retrofitting can be a game-changer, offering significant potential to reduce carbon footprints and usher in a more sustainable built environment when executed thoughtfully and strategically.

Redefining Sustainability Through Retrofitting

Sustainability in architecture has evolved beyond the creation of new eco-friendly structures. It now encompasses the responsible stewardship of existing infrastructure. Retrofitting, the process of upgrading and enhancing the performance of older buildings, offers an opportunity to breathe new life into the built environment. Sustainable architects are at the forefront of this movement, recognising that retrofitting aligns with the principles of resource conservation, reduced waste, and carbon reduction.

The Carbon-Reducing Potential of Retrofitting

One of the most compelling aspects of retrofitting is its potential to significantly reduce carbon footprints. Sustainable architects understand that existing buildings often have high embodied carbon, which refers to the emissions associated with their construction materials. By retrofitting, architects can extend the life of these structures, effectively “reusing” their embodied carbon. This reduces the need for new construction and mitigates the carbon emissions typically associated with it.

Preserving Architectural Heritage

Retrofitting is not just about carbon reduction; it is also a means of preserving architectural heritage. Many older buildings possess unique historical and cultural significance. Sustainable architects recognise the value of maintaining this heritage while making these structures functional and energy-efficient for contemporary use. This harmonious blend of preservation and modernisation represents a holistic approach to sustainability.

Energy Efficiency and Modern Comfort

Sustainable architects are adept at transforming older buildings into energy-efficient, comfortable spaces. They utilise cutting-edge technologies such as improved insulation, energy-efficient windows, and advanced HVAC systems to reduce energy consumption and enhance occupant comfort. By breathing new life into existing structures, architects make them relevant, functional, and sustainable for today’s needs.

Overcoming Retrofitting Challenges

While retrofitting holds immense promise, it comes with its own set of challenges. Sustainable architects are experts in navigating these hurdles, from working within existing structural limitations to complying with modern building codes and standards. They approach each retrofitting project as a unique opportunity to showcase their innovative problem-solving skills and dedication to sustainability.

Sustainable Architects: Champions of Retrofitting

Sustainable architects are the champions of retrofitting as a sustainable strategy. They understand that the built environment is a vast resource that can be harnessed to address climate change and environmental degradation. Retrofitting is not just about modifying buildings; it is about reshaping the future of architecture and embracing the transformative potential of existing infrastructure.

Chapter 8 Conclusion

In the pursuit of sustainability, sustainable architects are leading the way by emphasising the significance of retrofitting existing infrastructure. This approach expands the definition of sustainability, promoting the preservation of architectural heritage, reducing carbon footprints, and enhancing energy efficiency and modern comfort. Retrofitting is more than just a design strategy; it is a commitment to making the most of our existing resources and shaping a more sustainable, resilient, and harmonious built environment for generations to come.

Team at RISE looking at computer screen showing a model of building in 3D — ^{In the studio discussing the proposals for Herbert Paradise in Kensal Rise, NW London. On the screen you can see the model of the garden studio in 3D, all our projects are drawn up in ArchiCAD. BIM is like digital Lego instructions for real buildings. It helps people see, fix mistakes, share plans, save resources, and make changes easily.}

Chapter 9: The Role of Clients and Partnerships in the 2030 Climate Challenge

The success of the 2030 Climate Challenge is a collaborative endeavour that extends beyond the realm of sustainable architects. Clients, as key stakeholders in the architectural process, play an indispensable role in realising the ambitious goals set forth by RIBA. Their engagement, commitment, and willingness to collaborate effectively are pivotal in shaping a sustainable built environment. RIBA, recognising the importance of client involvement, offers valuable tools such as client guides to facilitate this collaboration and foster a shared vision of sustainability.

The Client’s Vital Role

Clients are more than just patrons of architectural projects; they are active participants in the journey towards sustainability. Sustainable architects understand that a client’s commitment to sustainability is a catalyst for change. Clients who embrace sustainability as a core value can inspire architects to push the boundaries of design and ensure that sustainability is integrated into every aspect of the project.

Buy-In and Shared Values

One of the first steps in achieving alignment between clients and sustainable architects is securing client buy-in. Sustainable architects advocate for open and transparent discussions with clients, ensuring that sustainability objectives are clearly defined and shared. Clients who align their values with sustainability goals are more likely to support innovative design solutions and sustainable building practices.

Collaborative Partnerships

Effective collaboration between clients and sustainable architects is the cornerstone of success in the 2030 Climate Challenge. Sustainable architects view clients as partners in the journey towards sustainability, valuing their input and expertise. Together, they work to identify sustainable design strategies, evaluate the environmental and economic benefits, and make informed decisions that align with the challenge’s objectives.

RIBA’s Client Guides

Recognising the pivotal role of clients, RIBA provides valuable resources such as client guides. These guides serve as informative tools that educate clients about the significance of sustainability and their role in the process. They offer insights into sustainable design principles, energy efficiency, and environmental considerations, empowering clients to make informed decisions that align with the challenge’s goals.

Sustainable Architects as Guides

Sustainable architects act as guides and advocates, helping clients navigate the complexities of sustainability. They provide clients with the knowledge and expertise needed to make informed choices that benefit not only the project but also the environment. Sustainable architects view their role as facilitators, creating a bridge between client aspirations and sustainability objectives.

Chapter 9 Conclusion

In the 2030 Climate Challenge, the role of clients and partnerships is pivotal in realising the vision of a sustainable built environment. Sustainable architects recognise that collaboration with clients is essential for success. Clients who share the values of sustainability and engage actively in the process can inspire innovative design solutions and promote sustainable building practices. With the support of resources like RIBA’s client guides, clients are empowered to make informed decisions that align with the challenge’s goals. Sustainable architects, acting as guides and advocates, navigate this collaborative journey, ensuring that the built environment of the future is not only sustainable but also a testament to the power of effective partnerships. Together, they shape a more sustainable, resilient, and harmonious future for all.

^{Douglas House in Kensal Rise, NW London, our low-energy home retrofit project included super insulation, airtightness, MVHR and Solar PVs.}

Chapter 10: The Path Forward: Continuous Adaptation and Growth

The 2030 Climate Challenge is a dynamic and ever-evolving initiative that exemplifies the spirit of progress and sustainability. Rooted in the ethos of environmental responsibility, it acknowledges that the journey towards a sustainable built environment is not static; rather, it is a continuous and adaptive process. Sustainable architects understand that the challenge’s targets and strategies are not set in stone; they will inevitably refine further as new research and sectoral insights emerge. As architects, our duty is to keep pace with these changes, embrace continuous adaptation and growth, and lead the way in sustainable design.

The Beauty of Evolution

One of the remarkable aspects of the 2030 Climate Challenge is its capacity for evolution. Sustainable architects appreciate that this challenge is not a rigid set of rules but a framework that evolves in response to emerging knowledge and shifting paradigms. It is a living testament to the architectural profession’s commitment to addressing the climate crisis head-on.

Ongoing Research and Insights

Sustainable architects are avid consumers of knowledge and information, constantly seeking to expand their understanding of sustainable design principles. They recognise that the field of sustainability is dynamic, with ongoing research yielding fresh insights into energy efficiency, carbon reduction, materials innovation, and more. By staying abreast of these developments, architects can integrate the latest advancements into their designs and projects.

Refining Targets and Strategies

The targets and strategies of the 2030 Climate Challenge will undoubtedly be refined further as new information becomes available. Sustainable architects view this refinement as an opportunity to push the boundaries of sustainability even further. They are ready to embrace more ambitious goals, incorporate innovative technologies, and adapt their practices to align with the evolving standards of sustainability.

Leading the Way in Sustainable Design

Sustainable architects are not passive observers of change; they are leaders in sustainable design. They understand that their role extends beyond designing buildings; it includes advocating for sustainable practices within the profession and guiding clients towards more sustainable choices. By embodying the principles of continuous adaptation and growth, sustainable architects set the standard for their peers and inspire a collective commitment to sustainability.

A Vision of the Future

The path forward in the 2030 Climate Challenge is one of unwavering dedication to a sustainable future. Sustainable architects envision a built environment where every structure is a testament to sustainability, resilience, and environmental responsibility. They see a future where sustainable design is not an exception but the norm, where architects play a pivotal role in shaping a world that is in harmony with nature.

The 2030 Climate Challenge represents a call to action and a testament to the power of continuous adaptation and growth. Sustainable architects, as the vanguards of this movement, are committed to embracing change, staying informed, and leading the way in sustainable design. They recognise that the beauty of the challenge lies in its evolving nature, and they stand ready to refine their practices, set more ambitious targets, and inspire a collective commitment to a sustainable future. As architects, they shape not only buildings but also the world we inhabit, leaving a legacy of resilience, sustainability, and growth for generations to come.

In conclusion, the RIBA 2030 Climate Challenge isn’t just a set of targets; it’s a clarion call for architects worldwide. Having been a part of the architectural community for two decades, I genuinely believe this challenge can galvanise our fraternity, and together, we can script a sustainable, carbon-neutral future for our built environment.

If you would like to talk through your project with the team, please do get in touch at mail@risedesignstudio.co.uk or give us a call on 020 3290 1003

Passive House – a luxurious way to take climate action

Posted on January 31, 2022 by RISE Design Studio

At RISE Design Studio, we work hard to minimise the environmental impact and energy consumption of our projects. One way we do this is by working with the Passive House and EnerPHit standards. In October 2021, publisher and editor of Passive House Plus magazine, Jeff Colley, gave a TEdx talk in Tralee on ‘How Passive Houses can improve your life and help the planet’. Jeff’s talk highlighted some of the key reasons why the Passive House is key to tackling the climate emergency.

What is a Passive House?

A Passive House (or Passivhaus) tends to use energy sources from within the building, such as body heat, heat from the sun or light bulbs, or heat from indoor appliances to create a comfortable, healthy living environment. Typically, a Passive House features high levels of insulation to roofs, external walls, ground floors (with no heat loss at junctions), triple glazing and air tightness. A ventilation system recovers heat from stale outbound air and passes it onto incoming fresh air that is then filtered when entering the house.

Your home is your sanctuary

In an increasingly uncertain world, we are often made to feel that taking climate action equates with making sacrifices in our lives. However, the Passive House shows us how climate action does not need to feel like this. Instead, it can improve life in several ways. Most importantly, a Passive House costs very little to heat (and in some cases nothing at all), and the internal environment always feel fresh and comfortable, whatever the weather.

The emphasis on ‘future proofing’ means that a Passive House can withstand any weather and/or temperatures that the future may bring. As Jeff Colley explains in his talk, people who live in Passive Houses regularly describe constant comfort, no ‘cursing at the cold’ in the mornings, and peace and quiet – acoustic performance is very high, making it hard to hear anything outside or between party walls in flats/other shared accommodation.

No need for heating

Impressively, there are many examples of Passive Houses whose residents rarely or never turn on the heating system. In some houses, a heating system is not even needed, with only small battery-powered back-up if required. For example, of 18 sheltered housing units built in Devon for elderly people, the heating had not been turned on in nine of the units five years after construction. Similar accounts relate to Passive Houses in which there has been a boiler issue but this is not an urgent problem, as in more standard homes.

A healthy home is a happy home

In the west, we spend about 90% of our time in our buildings, making it important that our home is a healthy place to be. Experiences during the pandemic have also made us think more about air quality and ventilation. Recent research in Ireland suggests that the benefits of Passive Houses go even further than reducing energy use and creating a comfortable living environment. Over 200,000 global lung cancer deaths each year are estimated to be caused by the presence of radon in buildings. This is a particular issue when the weather is cold outside and the indoor environment is warm – radon can rise up from the ground into the living environment. The average levels of radon in a Passive House have been found to be much lower than in an average home.

Drawbacks?

Some critics have questioned whether the Passive House standard restricts architectural freedom. However, the standard is remarkably flexible and accommodates good design, in both retrofit and new build projects. The standard can be applied to any building, including commercial and residential, and even listed period buildings.

The first Passive House hospital is nearing completion in Frankfurt and Passive House schools are becoming increasingly common, such as the Harris Academy in Sutton. Impressively, the standard has also been used in a very progressive council housing scheme in Norwich. The standard can be used to create a good indoor environment for ‘things’ rather than people as well. For example, an Imperial War Museum archive near Cambridge uses the approach to protect its artefacts for future generations.

Jeff Colley suggested that the main drawback of living in a Passive House is that it may become hard to stay in other people’s homes when one has become so accustomed to such high comfort levels. Joking aside, the Passive House is an excellent example of how ‘being green’ doesn’t have to mean sacrifice. As Jeff argues, it is one form of radical climate action that everybody can agree to. We fully support this argument and we continue to work with clients on new build and retrofit projects that apply the Passive House and/or EnerPHit standard.

Photo: Hervé Abbadie and Karawitz

Refurbishing homes for net zero – upskilling our design team

Posted on July 31, 2021 by RISE Design Studio

Refurbishing and retrofitting existing homes is a large part of the challenge of transitioning the built environment to net zero. We are faced with a significant task, especially as every home is different – efficiency measures that work in one home may not be appropriate for another. Retrofitting is also a daunting task for homeowners, particularly in terms of engaging a contractor with the right skills and experience for the job. At RISE Design Studio, we have worked on several projects that have included energy efficiency measures and, as the push to net zero becomes ever more critical, we are working hard to upskill our design team so all our projects are as energy efficient as possible.

Embracing refurbishment

The 2008 Climate Change Act committed the UK to reducing its greenhouse gas emissions by 80% by 2050. The buildings sector accounts for 37% of total UK GHG emissions and, of these emissions, 65% are from the residential sector. As a result, there has been growth in the residential retrofit industry, with buildings being adapted to be more sustainable and energy-efficient. The majority of our existing residential stock requires some level of retrofit to enable the government’s ambitious emissions targets to be reached.

Common measures include improving insulation. A new heating system might also be installed, or double glazing might be fitted. Yet, conserving energy is not the only reason to retrofit a building. Improving indoor environmental quality, reducing dampness and mould will all lead to increased health and productivity levels of residents.

Upskilling our design team

Recognising the increased momentum in London around reaching net zero, we have really enjoyed working with clients on refurbishment projects that incorporate environmental considerations. Modern architects are well-placed to add creativity and innovation into the drive to retrofit existing housing stock, particularly those that may prove very expensive to retrofit. For example, historic buildings such as Edwardian terraces are protected, and increasing energy efficiency can pose a real challenge. However, there are exciting options to retain the façade and rebuild the living spaces within the building.

More and more clients are seeking energy efficient homes and we are fully aware of the important role architects play in helping to reach the government target for 2050. As a result, we have been working hard to upskill our design team to work on these types of projects.

Maximising design benefit

There are several industry standards designed to increase the efficiency of residential property, including the Passivhaus and EnerPhit certifications. A Passivhau s project tends to use energy sources from within the building, such as body heat, heat from the sun or light bulbs, or heat from indoor appliances to create a comfortable, healthy living environment. However, it can be difficult to reach the exact requirements of the Passivhaus standard in a retrofit project.

Recognising this, the Passivhaus Institut has developed the EnerPHit standard for projects that use the Passivhaus method to reduce fuel bills and heating demand. We are working hard to implement this standard in our projects and our design team has developed the skills to align retrofit projects with this approach. EnerPHit takes into account the limitations associated with retrofit projects and relaxes some of the Passivhaus criteria to reflect this. Nevertheless, it is still a very demanding standard and generally results in a building that outperforms a new-build property both in terms of energy and comfort.