Timber crucial to carbon reduction, says Environmental Audit Committee
Using timber has been recognised as a crucial route to decarbonising our built environment in a new, landmark report from the Environmental Audit Committee (EAC).
The EAC has called on the government to complete a policy roadmap to scale up the use of timber in construction by the end of 2022 – at the latest – warning the UK is already falling behind their EU counterparts when it comes to reducing carbon emissions from the built environment.
Over 14 months of inquiry MPs heard from a wide range of experts on the best strategies to decarbonise the built environment – an area which is directly responsible for a quarter of the UK’s total carbon emissions – at a total of 177 MtCO2e – and strongly influences up to 42%.
Their report, ‘Building to net-zero: costing carbon in construction’, warns that despite the commitment of the UK Government to achieve a 68% reduction in the UK’s carbon emissions by 2030 compared to 1990 levels, there has been little to no leadership from Government on this issue.
To date, policies from the Government have focused entirely on operational emissions, those relating to day-to-day use of a building such as heating, while the embodied carbon emissions which arise from a building’s construction – despite sitting at some 40 to 50 MtCO2e – more than the aviation and shipping industries combined – remain ignored.
Evidence from a range of experts, including the UK Climate Change Committee, leading academics, researchers, architects and engineers showed that using timber in place of concrete, masonry, and steel is one of the most successful strategies to reducing embodied carbon in the built environment.
Researchers repeatedly highlighted the carbon saving potential of timber, saying that by replacing “a concrete frame and all brick and block houses with timber frame houses, you can reduce embodied carbon by about half,” and highlighting the need to grow the skills to support this shift.
The EAC also called on the Government to implement mandatory Whole Life Carbon Assessments, along with a clear timeline and targets for reducing emissions, to help create a push toward low-carbon materials and improve the sustainability of the built environment.
Independent evidence supplied to the committee from fire experts, architects, and engineering associations showed the post-Grenfell prohibition on the use of combustible materials in external walls has had a disproportionate impact on the use, innovation, and testing of structural timber.
A lack of distinction made between the cladding and primary structure within the ban on the use of combustible materials in the external walls of buildings above 18 metres was found to be particularly damning for the industry, causing a ripple effect which has set back all forms of timber construction.
Professor Michael Ramage (University of Cambridge) decried the ban noting that modern timber systems can and do deliver sufficient fire resistance within the primary structure, and how ‘one government policy [the ban] is making another government policy [net zero], untenable.’
The EAC called on Government to clarify their May 2020 consultation on the combustible materials ban and respond before the House rises for the 2022 summer recess, saying delays have left the construction industry ‘without the guidance and confidence it needs to invest in timber structures’.
Other actions to be taken now by the Government to reduce emissions include taking greater action through their procurement policies, supporting the industry to close the skills gaps, and promoting further research into the use of structural timber in the UK.
Confederation of Timber Industries chair Alex Goodfellow said:
“Timber is already a £10bn supply chain in the UK, which supports 350,000 jobs. It provides economic prosperity in every region of the UK, green employment, thousands of healthy, safe, warm, and beautiful low-carbon homes, and is helping create a sustainable construction industry.
“Right now we have an opportunity. We need to build more homes. We also need to make our existing homes more efficient, and reduce demolition. Timber can allow us to meet both these needs and rapidly decarbonise our built environment.
“By using more wood we can achieve quicker, higher quality, and safer construction, as timber lends itself to modern methods of construction by being manufactured offsite with factory precision, and extend the use of existing building, with light-weight timber structures able to lend additional stories.
“In addition, each time we use timber, it supports growing more trees. Timber keeps forests standing by incentivising landowners to engage in sustainable forestry, as for every tree harvested and placed on the market, several more trees are planted.”
Timber Development UK chief executive David Hopkins said:
“One of our biggest roadblocks to making the changes necessary to address climate change is a mindset which perceives the shift to a net-zero economy as down the road, in the future, and reliant upon unproven technologies to decarbonise the industries most responsible for emissions.
“We already have a solution. Wood is the only sustainable structural material which can enable substantial decarbonisation of the built environment based on existing business models and proven technology. It can provide vast carbon sinks in our rural areas and carbon stores in our cities.
“There is widespread industry agreement that using more timber in place of carbon-intensive materials, such as steel, masonry, and concrete, is the best route to reducing carbon emissions from the built environment. This report reflects that and calls on the Government to do more.
“As an industry, we are already taking up the challenges laid down in this report. Recently we formed Timber Development UK, merging the Timber Trade Federation and TRADA to form an organisation that can support the timber supply chain from supplier to specifier.
“From this position we are now setting out to empower all with the knowledge and confidence to use the world’s lowest-carbon building material – wood. By doing so we will close the skills gap and ensure that UK architects, engineers, and designers have the tools to succeed in building net-zero.”
Structural Timber Association chief executive Andrew Carpenter said:
“Our members provide an answer for how to build low-carbon in a climate crisis, as called for in this report. Offsite timber frame construction is an existing, long-established, high-value manufacturing and building method that delivers guaranteed quality, precision-engineered components.
“From Seattle to Stockholm to Sydney, timber frame systems are already the default choice for construction across almost all building types – small to tall. What we need now is greater consistency from the UK Government to give confidence to businesses to expand and take on investment.
“There are a range of policies which the UK Government can employ, many of which were outlined in this report. You only need to look across the Channel to the likes of France, which has mandated that all new public buildings must contain 50% natural materials.
“A large bank of data is out there already which shows how timber behaves in fire and demonstrates its safety, so while we welcome further funding for testing, we should not lose sight that timber frame systems are already an economic, high quality and safe solution to modern construction.”
