Before this week, few people truly believed you could use hardwood cross-laminated timber (CLT) to support an entire habitable building – not least the construction business. That’s why ‘The Smile’, on view in the courtyard of the Chelsea College of Art until mid-October, has become a landmark project for the London Design Festival.

Alison Brooks’ design, the culmination of 10 years of research by the American Hardwood Export Council (AHEC), uses industrial-sized CLT panels to create a gravity-defying pavilion the size of a London restaurant. The most ambitious CLT venture to date according to Arup, who engineered the project, it can support 60 people standing at the end of the 12m cantilever without so much as a tremor. Ordinary softwood would fall to pieces.

AHEC’s European director, David Venables, recruited London-based architect (and CLT devotee) Brooks to design the ‘live experiment’, and supplied her with a container-load of engineered tulipwood, a highly sustainable, incredibly low-density timber with a strong strength to weight ratio.

Speaking to visitors today, Brooks called the four-sided arc a ‘monument’ to the material. ‘It uses the wood in a way that exploits its material qualities and pushes it to the limit in terms of structural performance,’ she said. ‘And it allows you to experience it in an immersive way. It really communicates the essence of CLT.’

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