Wood Construction Under Fire After the First 6 Storey Wood Building in Canada Burns Down

richmond bc fire screen shot photo
Screen shot from youtube video

I do go on about how I think that wood is the most sustainable building material; instead of creating carbon dioxide, it absorbs it and stores it. I wrote recently in Sustainable Builder Magazine:

Wood is the ultimate renewable resource. Mikko Viljakainen of the Finnish Forest Industries Federation notes that, "In a country covered in forests like Finland, as much wood grows in ten hours as is needed for the annual construction in the entire country." It also theoretically has a negative carbon footprint, locking in the carbon dioxide absorbed while the tree was growing for the life of the building.

But the steel and concrete people were dancing in the ashes of the fire in Richmond BC a few weeks ago, when the first six storey wood buildings in Canada burned to the ground, suggesting that wood construction isn't safe or suitable for higher multifamily housing. One steel company said in their newsletter:

In June 2010, as the 188-unit project broke ground, Richmond Fire Department voiced concerns that they were not in possession of the necessary equipment to deal with a blaze in a wood structure of that size.

The uncompleted buildings were lacking their fire suppression systems, but the disaster has ignited fears that wood is unsuitable for such large projects.

"I wouldn't put my family in one," a local resident was quoted as saying.

But in fact, this was not a building fire; it was a construction fire. The wood structure was up, but no drywall, no fire separations and doors, and most importantly, no sprinklers yet.

The Canadian Wood Council jumped into the fray with a very long press release, noting that "To suggest that the outcome of the May 3rd fire at the Remy project in Richmond would have been the same if the building had been fully completed, is not plausible."

They also note that light steel framing and insulated concrete form construction systems also need to be fireproofed. Other points:

  • The fire safety of a completed building must consider the whole system, including the building contents and its use. For completed buildings, research shows that the size and severity of the majority of fires are related to the contents of a building and the living and working habits of its occupants.

  • In multi-family residential buildings, close to 80 per cent of fires are contained to the compartment of fire origin, regardless of construction type. In the few cases when fire does spread to the entire structure, such spread usually occurs at a time after the occupants have left the building.

  • No structure can ever be completely fireproof, and all construction materials can be affected by fire. Concrete and steel may not burn, but they can degrade and fail when exposed to a typical building fire, which could lead to a complete structural failure.

  • Heavy timber resists fire very well - when heavy timber burns, a layer of char is created, which helps to maintain the strength and structural integrity of the wood inside, reducing the potential for complete collapse.

wood response to fire image USDA Forest Products Laboratory (FPL)/Public Domain
image copyright FPInnovations, used with permission

In heavy timber and cross-laminated timber buildings, (which I consider to be the future of wood construction) it has been shown that the wood actually protects itself; the char acts as an insulator. Steve Craft, PHD, presented Fire Performance of CLT Assemblies (pdf here) and writes:

Large size wood members have the inherent
ability to provide fire resistance because of
the unique charring properties of wood:

- Burn slowly and forms char layer
- Non-charred wood retains significant strength
- Wood is dimensionally stable under fire conditions

wood is fireproof dimensions image
image copyright FPInnovations, used with permission

In fact, the engineers actually design it into the structure, making the wood members larger than they need to be, so that after the char layer forms, there is still enough wood do its job structurally. Fire protection is built right in.

The construction site fire in Richmond is unfortunate, but is not a "tragedy" as the steel suppliers call it; nobody was hurt and the owner is rebuilding. If we are going to build sustainably, we have to use more wood and less concrete, especially in Canada where we have so much if it under threat from beetle infestations. As I concluded in Sustainable Builder, " If we really care about our carbon footprint, our local environment and about jobs for our kids, we don't really have a choice."

Read the full press release from Michael Girioux of the Canadian Wood Council:
Fire Safety of Wood Buildings is not on Trial!
More on Wood Construction:
More Evidence that Wood and Natural Materials Store Carbon
Wood Makes A Comeback From Seattle to Bristol
Wood Construction Goes Seriously Vertical. But Does it Really Sequester Carbon?
Wood Construction Scales Up

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Tags: Wood Construction


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