UK fire tests to prove safety of CLT in large buildings.

THE British wood industry will spend $A965,000 on a series of fire tests over the next 18 months in a bid to demonstrate the safety of cross-laminated timber, ahead of a rule change that could see the product banned for use on the walls of large buildings.

CLT has been heralded in some quarters as the future of construction because of its low embodied carbon and the capacity to produce the panels offsite.

But the government’s plans to lower the ban on combustible materials in the external wall of a building from 18 m to 11 m would effectively restrict its use to low-rise projects only.

In an effort to demonstrate its safety, the three largest suppliers of CLT – KLH, Binderholz and Stora Enso – have invested in a series of fire tests to assess its performance.

The aim is to provide “a harmonised testing standard” and “enhanced understanding of fire resistance characteristics” of the product, a spokesperson for the Structural Timber Association said.

Data from the tests will be released as it becomes available, with the testing program set to last for 18 months.

The combustibles ban, introduced to ensure the safety of new buildings post-Grenfell, was the focus of lobbying from the timber industry when it was first introduced at 18 m.

As it applies to the whole of the wall construction, not just cladding, it effectively rules out using CLT in walls, although it is possible to use the building method in the internal structure only.

The Structural Timber Association is providing test-based research evidence of product performance that will enhance the understanding of fire resistance. CEO Andrew Carpenter said this extensive research would be completed within 18 months and “we intend to release the data as it becomes available during the testing program”.

Meanwhile, in Australia, flammable cladding needs urgent attention as the NSW government is accused of dodging the seriousness of the issue, with only a small portion of at-risk buildings made safe.

A NSW upper house committee has released its report into the regulation of building standards and disputes, following high-profile building defect issues in NSW and building fires involving flammable cladding interstate and overseas.

“Flammable cladding has been responsible for fires spreading quickly through a number of buildings around the world and for loss of homes and lives,” the report says.

“It is only a matter of time before NSW experiences something similar.

“It should not take a building fire here for the government to act comprehensively to address this problem.”

The report said it was clear only a small minority of buildings with dangerous cladding had been made safe – despite the state government’s 10-point plan for fire safety.

Committee members and coalition MPs Trevor Khan and Natalie Ward said it was a time for “thoughtful and constructive steps” towards building confidence in the industry, rather than “political point-scoring and grandstanding through the presentation of a potpourri of thought bubbles and empty gestures”.