Ontario building codes changed last year allowing for a maximum height for wood-framing from four stories to six.
This happened, according to the Ministry of Municipal Affairs and Housing because new safety requirements for wood-framed buildings include building stairwells with non-combustible materials and roofs that are combustion resistant.
From the ministry’s standpoint, the changes will make homes more affordable and supports “more attractive, pedestrian-oriented buildings that enhance streetscapes.”
The argument is that wood construction is less costly than competing methods such as concrete or steel. Presumably these cost savings will be passed on to the consumers. These buildings however, may be more expensive to insure than those built with other materials. So what is gained in cost savings using wood can end up being lost in the cost of providing fire insurance protection.
Why Is This?
Wood proponents argue that wood is as safe as steel or concrete when dry wall installation has been completed and, in taller buildings, sprinklers have been installed. Obviously providers of fire insurance disagree.
So Do Fire Fighters
Scott Marks of the International Firefighters Association said, that increasing the amount of wood in a structure increases the fuel load. He points to the number of fires in wood buildings while they are under construction. One such fire in Kingston, ON last year forced the evacuation of nearby buildings and residents were not able to return home for some time. The onset of the fire was so rapid it stranded a crane operator who subsequently had to be rescued by helicopter.
Vulnerable Under Construction
Wood-framed buildings are most vulnerable when they are under construction as with the fire in Kingston. This is true mostly because dry wall has not been applied but there are other potential fire hazards such as sawdust and wood remnants that may litter a site .
Proponents of wood say buildings of wood-framed construction are just as safe as ones built with concrete or steel. But even they qualify statements about fire safety with the qualifier that wood-framed buildings are just as safe as buildings constructed with other materials when construction is complete.
In short, while under construction and perhaps even when completed, six-story wood-framed buildings are not safe. They are fire hazards and can be a danger to anyone working on the site or living nearby.