Cross-laminated timber (CLT) in 2017
Published Thursday 21st September, 2017
We’ve all been rooting for the popular-growing cross-laminated timber (CLT), and 2017 looks like it’s the year that the timber product places itself firmly in the market as a leading construction material.
Here, we’re going to take an in-depth look at CLT and find out just how and why CLT, in the words of one architect, has prompted a revolution in housing construction.
Firstly, here’s a quick recap from our previous blog on what exactly cross-laminated timber is.
Cross-laminated timber is made by layering three, five or seven timber sections of wood at right angles, then gluing them together to form structural panels, which gives it a steel-like strength. It can be prefabricated in a factory to any shape or dimension, and is lighter than its steel and concrete counterparts.
CLT was born in Austria and Germany in the early 1990s, but only recently made headway in the mainstream market – in 2015 the USA began to manufacture it, and the UK still imports. However this doesn’t mean that we’re behind in the trend – Hackney alone has 23 buildings made largely of CLT, whilst the Financial Times said about London:
“It is at least at the cutting edge of a new timber architecture.”
Sustainability, safety and cost-saving
In a recent publication about CLT, author Christiane Varga said that if you replace a steel floor structure with one made from a wood-based material, like CLT, the carbon footprint can be reduced by almost 10 tonnes of Co2 for every tonne of wood used.
As well as this, mass timber is inherently resistant to fire, meaning that we would be protecting ourselves as well as the environment. As the founder of dRMM, Alex de Rijke says:
“Timber has proved itself, it’s the world’s oldest building material.”
And more savings can be found with CLT cost-wise. In the construction of the world’s tallest CLT building, the use of the wood-based material meant savings of up to 15% on the cost of the project. Plus, the ease of construction and off-site fabrication meant that the number of deliveries during construction was cut by 80%.
In the press
It is this added safety, sustainability and cost-saving that places CLT at the forefront of leading developments.
The most prominent example is Waugh Thistleton’s Dalston Lane in London, one of the world’s tallest CLT structures, with CLT making up the external, party and core walls, floors and stairs.
Completed this year, the project has already been commended at several construction awards, making the 10-storey, 121-unit development the current centrepiece of the industry. It weighs just a fifth of a concrete building of this size which is what made it possible to transform the neglected brownfield site into a habitable site. Considered carbon negative, the structure’s embodied carbon is an amazing 2.5 times less than that of an equivalent concrete frame.
It isn’t only in the UK that CLT is making its mark however with Brock Commons, a 174-foot tall, 18 storey accommodation unit at the University of British Columbia, opening in July of this year and taking the title of the world’s tallest mass timber building.
As architect Simon Speigner observes in The future of Timber Construction: CLT: “CLT is an Austrian invention that prompted a revolution in housing construction.”
And in the words of Andrew Waugh, of Waugh Thistleton Architects, CLT “gives us the buildings we deserve, rather than the ones we put up with!”
If you’ve got any questions about the use of CLT or would like to share some great examples of mass timber in construction, we’d love to hear from you – so get in touch on Twitter.