Fears of fire after Grenfell tragedy are holding back switch to sustainable building materials like engineered timber, architect says
Fear of fire in the wake of the Grenfell tragedy is holding back a switch to more sustainable building materials, a leading architect has told Sky News.
Andrew Waugh of Waugh Thistleton Architects, which is at the forefront of eco-building design, said the construction industry and regulators are too cautious about using engineered timber in tall structures – even though the catastrophe was in a concrete tower.
“We are being held back,” he said.
“(The UK) were the innovators of this material before Grenfell happened.
“Now we have a situation where the rest of the world are changing their building regulations, changing their planning laws and government procurement for housing, hospitals and schools to promote the use of timber.
“And we are alone in the UK in not doing anything to promote the use of timber.”
Mr Waugh designed the new six-storey Black and White Building in east London, the UK’s tallest office block constructed from engineered timber.
Columns and beams are made from cross-laminated timber – layers of wood that have been glued together at different angles – making them stronger than concrete and lighter than steel.
Both Norway and the United States have recently built skyscrapers from the material that are more than 80m in height.
But in the UK, structural timber can only be used in buildings up to 11m tall – or up to 18m if there is a sprinkler system.
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Experts are divided on the risks of engineered timber in a fire. Some argue that the exterior surface only chars, leaving the structural core intact.
But Rory Hadden, a fire safety researcher at Edinburgh University said charring still releases combustible gases – and more studies need to be done.
“I want to see timber buildings. The benefits of them are real and they’re nice places to be,” he said.
“But the worst-case scenario for me is if something goes wrong just once, and there is a significant fire, the reaction will be to ban the materials and then we can’t drive those benefits anymore because we’ll be up against a huge hurdle to overcome.”
The construction industry is responsible for almost 40% of global carbon emissions. Cement alone accounts for 8%.
But timber is a carbon sponge. A tree sucks 1.8 tonnes of carbon dioxide from the atmosphere to produce 1 tonne of timber.
As long as the wood is intact, and doesn’t rot or burn, the carbon is stored long-term.
Greensted Church in Essex is the oldest wooden building in Europe, with some of its structure dating back more than 1,000 years. The trees used to build it would have been absorbing carbon dioxide from the air around the time of the Vikings.
Mr Waugh said a new wave of timber buildings could make a significant impact in the climate crisis.
The Black and White Building has more than 1,000 tonnes of carbon locked up in its structure.
“We need to be transforming our entire construction industry to one that is dominated by a timber architecture,” Mr Waugh said.
“We can’t keep using the Earth’s resources and build buildings (from steel and concrete) that are very hard to adapt.
“We can move timber buildings around, unscrew them and cut holes in them very easily.
“So the adaptability of these buildings, the low carbon qualities of this material and the fact that we can grow more of it mean that timber is the future of architecture and the future of construction.”
Professor Michael Ramage, director of the Centre for Natural Material Innovation at the University of Cambridge, said 80-90% of buildings of 15 storeys or less could be constructed from timber.
“The world population is growing and it is growing predominantly in urban centres,” he said.
“Everything we build now is probably going to be with us for 40 or 50 years so this is an opportunity to lock in a sustainable way of building rather than continuing with the materials we know are bad for the climate.”
Building with timber is quick and clean compared to concrete.
It took four people just 14 weeks to bolt together the frame of the Black and White Building.
But mortgage companies and insurers take more convincing to back what they still see as a novel material.
Charlie Green, one of the founders of the Office Group, which rents out space in the building to companies, said: “It requires a mindset change from the industry to respond to what occupiers want.
“There are certainly risks in building in this way. Those come in the form of funding, which we secured, and insurance for fire and water damage.
“It’s about starting those relationships early on, giving comfort that this is being constructed in the best way possible and that we are doing more than we need to to satisfy the concerns of the insurance community.”