Refurbishing homes for net zero – upskilling our design team

 

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.

Retrofit flat London

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 Passivhaus 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.

Sustainable architecture principles: environment, energy, efficiency

 

Buildings account for about half of the UK’s carbon dioxide (CO2) emissions. Globally, architecture was responsible for 40-50% of waste deposits in landfills at the turn of the new millennium, and 20-30% of greenhouse gas emissions.

The environmental integrity of a building (i.e. how it is designed and operated) is now a key consideration in the design of new buildings and the renovation of existing ones. More and more architects and designers are realising that good design improves quality of life and minimises harmful impacts on our health. Clients are also seeing the benefits of more environmentally responsible buildings through future-proofing, reduced operating costs, and comfort and health benefits. As a result, we are seeing more ‘sustainable architecture’ projects, which seek to minimise the negative environmental impact of buildings by efficiency and moderation in the use of materials, energy and development space.

Sustainable architects

So, what are the three main characteristics of a sustainable architecture project?

Environmentally-friendly building materials
A sustainable architect typically chooses to use environmentally-friendly building materials. The most desirable materials are those that are recycled or renewable, as well as those that require the least energy to manufacture. There is often a focus on using locally-obtained woods and stone, reducing the distance that materials travel before being used in the construction process and supporting local trades. There is a preference for wood that is harvested responsibly from certified forests and all other materials are non-synthetic and non-toxic. Recycling is at the heart of a sustainable architect’s design. Although recycled building materials were difficult to source in the early 1990s, there is now an active trade in recycled architectural salvage, particularly by specialist companies providing materials from demolition sites.

Energy and resource efficiency
Sustainable architecture is underpinned by a philosophy that advocates sustainable energy sources. Where feasible, steps are taken to design for energy efficiency, including the use of renewable energy sources such as wind, geothermal and solar. A sustainable architect recognises that the energy efficiency of buildings can be increased in a variety of ways. A building can be oriented to take full advantage of seasonal changes in the sun’s position, and energy-efficient lighting and appliances can be installed. Energy conservation is also key: buildings can be ‘weatherised’ for maximum protection against the loss of warm or cool air, and appropriate insulating materials and window glazing can be installed to reduce heat loss in ways that do not cause indoor humidity.

Efficient use of space
The sustainable architect recognises the importance of indoor environmental quality for affecting how an individual feels in a space and focuses on features such as a healthy indoor environment with adequate ventilation, temperature control, and the use of materials that do not emit toxic gases. The incorporation of earth shelters, roof gardens, and extensive planting throughout and around buildings is also encouraged. In the UK, a study by CABE (Commission for Architecture and the Built Environment, now Design Council Cabe) of five new academic buildings and campuses found that more than 70% of staff and students believed that the facilities and functions of the buildings they work in improved the way they felt and behaved.

Buildings built to the Passivhaus standard are a great example of these sustainable architecture and design principles in practice. We’ll be writing more about Passivhaus in our next post.