We are facing a global housing crisis.
Projected population levels according to the UN will reach 8.6billion by 2030, with 96000 affordable new homes needed to be built daily to house the estimated additional three billion.
It is expected that the creation of these homes will be in urban areas, with resulting megacities, a modern phenomenon in which 630million will live in forty cities worldwide.
These are eyewatering statistics, and they present a pressing question for society.
As we face an ever-ageing population, unaffordable housing, and drastic population growth, how do we create buildings which meet this demand but in so doing do not contribute to the colossal environmental damage caused by the built environment?
In this blog we examine the rise in popularity of timber construction to find out how ‘using wood for good’ could be the answer.
Climate change and the global housing crisis
When it comes to climate change, we are at a defining crossroads, and the built environment has a crucial role to play in where we go from here.
Globally approximately 20% of greenhouse gas emissions come from building materials and related construction, with another 27% from the operations of these buildings.
To create what is needed in terms of housing and infrastructure without a catastrophic effect on our environment would appear to be impossible.
There is significant pressure therefore on the construction industry and everyone involved to find alternative building materials to cement and concrete, which in themselves account for 11% of gas emissions, iron, and steel another 10%.
It is this very real scenario that has led to the accelerated interest in the use of timber as a viable construction and design option and a climate friendly solution to what we now face.
The history of timber in UK construction
One of the oldest known building methods, we can trace the use of timber in UK construction back centuries, with archaeologists discovering remains of timber framed homes dating back as far as 10,000 years.
This was in part down to the plentiful supply of strong and durable English Oak which lasted until the 17th century when it became required for ship building.
The Great Fire of London in 1666 and the subsequent London Building Act 1667 saw timber facades banned in the City of London and stated the use of masonry in its place, this meant that certainly in the capital its use faded.
Such was the power of this legislation that the use of timber within the City of London all but vanished until the redevelopment of the Globe Theatre in 1997, a building constructed entirely of English Oak with no structural steel.
However, throughout the rest of the UK timber remained an important building method from the 1600s until the Victorian era with the renaissance of brick and stone, and the Industrial revolution which saw mass produced concrete, iron, and steel replace it as ‘practical, affordable, and feasible’ alternative.
Timber use in the modern world
The 1990s saw the advent of Cross Laminated Timber (CLT) first developed in Austria and championed by researcher Gerard Schickhofer through his work at Graz University’s Institute of Timber and Wood Technology, the Institute he began in 2004.
His work on the potential of these laminated timber panels placed perpendicular on top of each other culminated with his theory-focused thesis in 1994.
He compared its behaviour to that of plastic panels, focusing on cross layering of wooden panels which up to that point had received little in the way of engineering focus. It was through this research that he discovered the potential such timber materials had for commercial use.
This research work came at a time when other people were looking into timber panel systems, including Merk a Bavarian timber company, and Pius Schuler who subsequently set up a company specialising in three panel systems for domestic housing.
Schickhofer’s research examined the strength, optimum pressure, and application of the panels and their different configurations, to meet technical standards and European strength grades. It also looked at which adhesives would be most effective.
The results of the testing were submitted in mid-1996, with approval for further research and the first CLT production granted by the Austrian Government in 1998.
Early use saw it incorporated into bridge projects such as the Kohibacher bridge, and operational production lines coming into place. This led to the testing and development of pilot, regional and national CLT projects including the Federal Forestry HQ in Vienna.
The early to mid-2000s saw Germany, Norway, Sweden, and the UK through the pioneering company Eurban look to develop large scale solid timber projects.
Widely used across Europe, Australia, and Japan, momentum is now gathering in the USA with CLT incorporated into International Building Code in 2015.
Here at RISE Design Studio, we recently designed a zero-carbon sustainable yoga retreat in Norway’s Lake Krøderen, using a timber frame construction which perfectly complements its mountain and lake setting.
The world’s tallest CLT building is currently Brock Commons at the University of British Columbia, 174feet high, the 35 story Baobab building in Paris is underway and research is progressing to build an 80 story timber framed structure a ‘plyscraper’, Oakwood Tower in London.
What is Mass Timber?
Mass timber is engineered wood, a next-generation forest product which is natural and renewable.
It involves attaching softwood (pine, spruce, or fir) or hardwood (birch, ash, or beech) together to form thick compressed panels or structural elements such as posts or beams.
Lamination, adhesives, or fasteners holds the panels together. This results in timber that is strong, fire-resistant, and lightweight.
Mnaufacturing for load bearing wall, roof and floors, tends to happen off-site particularly for taller wood building projects.
There are two types of mass timber:
Cross Laminated Timber (CLT) – this is the most popular type of mass timber. It is formed by compressing three to nine dried lumber boards cut from a single log into bonded together layers. The grain in each lies perpendicular to each other.
Adjustments to the depth of each panel occur by changing the number of layers and multiple panels that are joined together. It is this structure which gives it strength allowing its use for floors, walls, ceilings, and buildings.
Glue Laminated Timber (Glulam) – here the lumber boards are arranged with the grain running in the same direction. Used mostly for beams and columns, it can be readily formed into curved shapes.
There are other forms such as dowel laminated timber, nail laminated timber, and parallel strand lumber.
What are the advantages of mass timber in construction?
Increasingly mass timber is seen as a safe and real alternative to traditional building methods which use concrete and steel.
With the Paris agreement setting targets to restrict global warming to 1.5degrees, one of the most prolific advantages is that mass timber can reduce a buildings carbon impact and in turn lower greenhouse gas emissions.
A number of experts advocate this approach most notably scientist Hans Joachim Schellnhuber founder of the Potsdam Climate Impact Research Institute and Bauhaus Earth.
It is his belief that in harvesting timber to build the cities of the future, you achieve the promotion of forest growth, and substantial amounts of stored carbon can be held in buildings for the long term. This is due to trees ability to absorb and store carbon in their trunk for hundreds of years, even after felling and manufacturing takes place.
Bauhaus Earth’s cemented its focus on the rapid transformation of construction as it relates to environmental impact taking it from ‘climate villain to climate hero’ at their ‘Reconstructing the Future for People and Planet’ conference held at the Vatican in June 2022.
The fundamental approach is that by building with timber you are creating a carbon sink whereby more carbon is absorbed than released. Sustainable forestry practices would see the associated growth and preservation of forests themselves the largest land-based carbon sink.
Recent academic research as published in the Journal of Academic Engineering in July 2022 supports this. It states that there is approximately a 40% reduction in carbon footprint when using CLT in comparison to traditional materials on a multi-story project.
There are also lower emissions associated with the production and manufacturing of a wooden building as opposed to one made from steel or concrete. End of life disposal when the building use ends also results in less emissions when compared to a traditional build. Some research states 50% to 80% less.
Other key advantages of working with mass timber are:
Timber construction in London and the UK
It would appear in recent years,’ that London has embraced timbers sustainable and aesthetic benefits as illustrated by a variety of high-profile projects:
However, in September 2021 the London Mayor announced a set of conditions for those applying for cash from the new Affordable Housing Programme that mean combustible materials are not now used in external walls.
This limits the use of mass timber products including CLT, grouping them together with combustible cladding.
There are those within the architectural and design industry that view this as a step backwards, with concrete and steel yet again the ‘go-to’ and timber pushed aside without proper consideration given to implementing new standards and regulations when it comes to its safe use.
Elsewhere in Europe and the UK, timber frame construction for new homes continues apace. From bespoke residences in the Isle of Skye to stackable homes for the homeless in Wokingham.
In Scotland, where 2025 targets are for all new build homes to be ‘zero carbon ready’ over 85% of those properties new to the market have timber frames.
Why you need an architect for your timber frame construction
With more individuals considering timber frame construction for their bespoke residential or commercial projects, it is important to look at the benefits an architect will bring to the design and the overall result even when using a prefabricated frame.
The benefits of mass timber when it comes to construction, the environment and the future of the built environment are far reaching. It represents a forward-thinking approach, a socially responsible way of constructing and a high performance and innovative way to navigate the challenges we face.
Whilst some remain doubtful that it can take on the might of concrete and steel, it appears that mass timber is not only here to stay but will indeed prove to be a worthy competitor, and one we may not be able to do without.
For further information on timber construction and design please contact mail@risedesignstudio.co.uk or give us a call on 020 3949 8471
RISE Design Studio Architects company reg no: 08129708 VAT no: GB158316403 © RISE Design Studio. Trading since 2011.