There have been 462 fires at construction sites over the past decade across B.C.; blazes that killed two people, injured 16 and caused over $100 million in damages and losses.

Surrey Fire Chief Len Garis said almost half of them were “incendiary,” meaning likely caused by arson, or otherwise suspicious, and he and other fire officials are calling on construction sites to improve security.

“One of the leading causes of construction fires is incendiary, although the numbers are declining year over year,” he said.

Fire officials in White Rock are trying to determine what caused a massive fire that started at a construction site. The blaze spread to a neighbouring apartment building and forced 100 people out of their homes.

An analysis by fire-protection firm CFT Engineering of construction-site fires from 2005 to 2009 found the majority of incendiary fires happened overnight, between 5 p.m. and 4 a.m., said owner Brad Walton. “This indicates that the after-hour security measures provided did not deter incendiary acts to the same extent as the presence of workers on site,” he said in a 2012 report.

Garis and Walton said fire prevention and safety at construction sites has been improving, but there is still work to do.

Walton said 2012 changes to the fire code to ensure construction sites have fire-safety plans has helped.

Garis said “best practices” for fire safety at construction sites have been around for about 18 months and more sites are using prevention techniques, such as fire-suppression tools, keeping the area free of debris, a hazardous operations policy, no-smoking rules, and better and round-the-clock security.

But despite the spectacular size of a condo construction site, neither Garis nor Walton said those sites are at greater risks than other places.

Garis noted that construction-site fires made up less than one per cent of all B.C. fires over the past 10 years.

But partly built structures are more likely to burn to the ground because they have none of the usual fire prevention or suppression safeguards, such as alarms, sprinklers or firewalls. Once fully engulfed, there’s not enough water to control the fire, and firefighters can only work on preventing the spread of flames.

The 150 residents of a Langley townhouse complex who were forced out of their suites exactly a year ago when a rental building burned down next door know the fear of spreading flames.

“A lot of the residents were traumatized,” said Cheryl Carlyle, president of the strata council at the Murray Green townhouse at 49th Avenue and 220th Street, which was hit by an overnight fire in 2015.

Carlyle said the rental building next to Murray Green is being built again after the fire and she’s relieved to see a watchman on overnight and locks on the fences, where before they had none, even though her and her neighbours never did learn the cause of the blaze next door.