Colindale fire questions safety of timber-frame sites

A timber-frame housing development under construction in north London burned to the ground in less than nine minutes, a Building investigation has revealed.

The findings of a London Fire Brigade (LFB) inquiry into the fire that ripped through the Beaufort Park development in Colindale on 12 July has raised questions about safety procedures on timber-frame developments.

A meeting in December to discuss the findings could lead the Health and Safety Executive to publish new guidance on how firms should protect construction sites from fire.

In an exclusive interview with the LFB, Stephen Robinson, the group manager of the fire engineering department, said little can be done to save half-constructed multistorey timber buildings from total destruction. “If an unfinished building like this catches fire, it will spread more quickly than the fire brigade can intervene,“ he said.

The fire is understood to have started accidentally in a building consisting of a structural timber frame and roof. It burned rapidly and radiated vast amounts of heat owing to the lack of protective external cladding.

The LFB and other experts have warned that the uncontrolled spread of this fire means a new approach is needed for multistorey timber-framed construction sites.

“With timber-framed buildings of this size you need to take a different approach from steel or concrete during construction,” said Peter Bressington, the director of multidisciplinary consultant Arup’s fire engineering department.

“If there’s a fire in a concrete or steel building it wouldn’t be an issue, but in a timber-framed building you would lose the lot.”

Bressington said it was the Construction (Design and Management) supervisor’s job to consider risks specific to timber-frame early in the design process and to mitigate these.

He said: “If it’s flagged up that a development is going to be built from timber, it should trigger a process. [The programme] should address the time the building is vulnerable. For example, you should get the fireboarding on as soon as possible. You also need to reduce the fire load and ignition sources on site.”

The HSE said it was “aware of the particular health and safety issues during the construction of timber-frame buildings” and was “working with the industry to help them manage these risks”.

Bryan Woodley, chief executive of the UK Timber Frame Association (UKTFA), said there were no special problems with timber-frame construction, noting that “all building methods have their areas of vulnerability”.

But he said the UKTFA was due to meet with the LFB and HSE in early December. ”If Colindale shows extra measures are needed, we will look at that,” he said.