Blaze in north London began when a spark ignited sawdust

A fire that ripped through a north London school has sparked off a £4m compensation claim.

Harrow council and Bentley Wood High School are suing contractor Procare Building Services for a blaze in August 2007 that started when a spark ignited a pile of sawdust.

They believe the spark was caused by a nail or staple being caught in a sander or by a discarded cigarette, and claim Procare failed to adequately mitigate the risk and train its staff properly.

Ten fire engines fought the blaze. The top floor was gutted, while smoke and water damaged the lower floors.

Kier Group was called in to repair the damage. Meanwhile, classes took place in 14 temporary classrooms. Twenty new classrooms and seven science laboratories were opened in July 2008.