If you stacked a pile of wood in a fire pit and then threw a match in the middle, would you be surprised if it caught fire and burned? Probably not.
So why would it surprise anyone that the recent rise in the use of wood framing for mid-rise construction projects has been accompanied by a steadily growing catalog of catastrophic fires in many markets across the nation?
Before I’m accused of being a little hysterical, the campfire/wood-framed building analogy was first presented by a reporter at The Oregonian (Portland, Ore.) newspaper following a blaze that destroyed the Monroe Apartments in Portland that were under construction in 2014. The architect who designed this project and many others like it in the Pacific Northwest also acknowledged the propensity of wood to burn. “You’ve got this giant stack of kiln-dried wood just waiting for a match,” according to reports in The Oregonian.
The risk associated with wood framing in these buildings is significant. Scott Marks with the International Association of Fire Fighters is quoted as saying: “The increase in the amount of wood in the structure increases the fuel load. When you start to tally up the wood in those buildings there is an incredible amount of potential fuel load for a fire. And because of the higher combustible load, incidents go from incipient to catastrophic in very short order.”
When one of these fuel-heavy buildings turns into an urban forest fire, it creates hazards to nearby property, as well. In Los Angeles, the blaze that destroyed the DaVinci apartment complex shut down two freeways and damaged at least four nearby buildings. The fire that burned the mid-rise, wood-framed apartments in Madison, Wis., in August 2014 was so hot it melted the vinyl siding on nearby houses and was observed on weather radar. As more mid-rise, wood-framed buildings go up, firefighters increasingly are required to manage or extinguish fires that spread to adjacent buildings, which happened earlier this year in a number of other locations.
Sadly, the 2014 fire in Portland was only one in a string a major, headline-grabbing fires that have torched huge mid-rise, wood-framed buildings as they’ve gone up in New Jersey, Texas, Washington, Wisconsin, California, Missouri, Utah, Maryland, Massachusetts and Canada-anywhere wood has made inroads into mid-rise construction.
The trend toward using more wood framing in mid-rise buildings has been enabled by a recent movement to relax or change building codes to permit wood framing at heights above the typical four-story limits, and driven by a pursuit of what builders believe are cheaper construction methods and materials.
Now with the growing body of evidence of significantly higher risks associated with this type of construction, it’s time for the construction industry to take a closer look at building codes, which until 2008 would have required buildings six stories or higher to have non-combustible exterior walls from top to bottom.
Insurers have long been wise to these risks. Wood construction has a greater likelihood to burn or be damaged by fire, and will more likely result in a total loss versus a partial one. Loss history for wood construction has been poor, and carriers are very restrictive of the amount of risk they will take (known as capacity). This drives up the cost to the builder, and actually weakens the argument that wood is less expensive than other materials. The recent major wood-frame fires have caused a number of major carriers to review their underwriting policies, and it will be interesting to see how they adjust their premiums for wood-frame construction in light of the major claims these fires represent.
To be fair, those who are promoting wood framing in multistory construction note that most of these major fires have occurred while the building was under construction-the most vulnerable phase. In simple terms, they argue that once the sprinklers and fire-mitigation systems are in place, wood-framed buildings are as safe as concrete or steel structural systems.
But what happens when the gypsum wallboards used for fire protection assemblies are subjected to the normal structural strains of a building after it is completed? How about the wear and tear of occupants who damage walls in occupied spaces, ranging from doorknob holes to cracks and unauthorized remodeling? And what happens when part of a building’s wood structure is exposed for months during renovation, including periods of time when adjacent units are occupied?
We’re now starting to get answers to those questions. In January 2015, the four-story, woodframed Avalon at Edgewater apartment complex in Edgewater, N.J., was largely destroyed by a fire started by maintenance workers doing plumbing repairs. Their torch ignited the wood studs inside the wall and the flames spread inside the cavity- outside the reach of the sprinkler system-and into the roof.
The significance of this fire is that the building had been completed and occupied since 2002. The sprinkler system was operational. The gypsum wallboard was in place until it was breached during routine maintenance.
It makes me wonder how many other timber time bombs will be built before a truly catastrophic event occurs.
There is good news. Following the New Jersey fire, legislation has been introduced to examine the building codes and possibly introduce some common sense restrictions or regulations that protect the public. The Los Angeles City Council will soon hear public comments on changes that should be made to the building codes in that jurisdiction following the DaVinci fire last December. Longer term changes have been proposed to the International Building Code.
All companies have competitive pressures, and the pursuit of new technologies, methods and materials that offer cost and time savings is how we all stay in business. The building code evolves to accommodate these new approaches. But there are times when changes to rules and regulations overshoot the target. Perhaps we’ve reached that point with the changes instituted in the last decade that have allowed bigger and taller wood-framed buildings. The time to answer that question is now.
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Larry Williams is the executive director of the Steel Framing Industry Association. For more information, go to www.cfsteel.org.