'Re-Thinking the Building Codes - As Fires Level Wood Framed Buildings, the Steel Industry Fights for Safety' - AWCI's Construction Dimensions - April 2015

Date: 05/08/2015

 The recent movement to relax or change building codes to permit wood framing at heights above the typical four-story limits has been driven by the relentless pursuit of cheaper construction methods and materials. And credit the wood industry for capitalizing on the economic pressures many builders face by successfully introducing three very significant revisions to the 2006 model building code. 

 
The first of these changes increased the allowable heights of wood framed buildings from 50 feet to 70 feet. Another crucial revision was to allow fire walls constructed of combustible materials (wood) to be used in Type V buildings, which prior to then had required non-combustible (steel) or fire-resistive (concrete). The justification was that once the sprinklers were installed and the fire-resistant gypsum board was applied to the framing member, it didn’t matter what was in the wall cavity. The third important change was in the evolution of the definition of a fire wall. Starting in the 2006 codes, a fire wall was no longer considered to be just a separation of fire areas within a building, but also to allow the division of the structure into separate buildings, each subject to its own height and area limits. 
 
Together, these revisions have enabled the proliferation of large multifamily and retail projects where structures up to 70 feet tall are being built with five stories of combustible wood framing installed over a one- or two-story podium of noncombustible steel or concrete. As stated in wood industry promotions: "It (changes to the building codes) opens many new opportunities for design using wood-frame construction.” 
 
I Told You So 
But these changes have had predictable results, as the chronicle of devastating fires in mid-rise wood frame buildings continues to grow. Witness the huge fire that destroyed the DaVinci project in Los Angeles in December, which has been closely followed by an enormous blaze in New Jersey that destroyed the Edgewater apartments and displaced 1,000 residents. And let’s not forget the huge Mission Bay 360 project in San Francisco that burned to the ground less than a year ago. Or, the fires in Houston, Canada, Portland, Maryland, Madison, Utah, Missouri—the list goes on. Is it a coincidence that all of these structures were four and five stories of wood framing on top of two-story concrete and steel parking lot? 
 
The Steel Framing Industry Association applauds the call by Los Angeles City Councilman Bob Blumenthal to review the building codes that up until 2008 would have required buildings six stories or higher to have non-combustible exterior walls from top to bottom. SFIA also commends a study by LAFD Chief Joseph Castro’s Fire Commission as to whether changes should be made to the building codes. There are good reasons why this study should take place. 
 
The risk associated with wood framing in these buildings is significant. Says Scott Marks with the International Association of Fire Fighters: "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.” This view is also echoed in a handbook published by the National Fire Prevention Association: "From a firefighter’s point of view, lightweight wood-frame construction is a campfire waiting to happen. A fire in this type of construction will spread rapidly throughout the building and to adjacent exposures.” ("Fundamentals of Fire Fighter Skills,” Third Edition, David Schottke). 
 
Urban Forest Fires 
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 DaVinci fire shut down two freeways and damaged at least four nearby buildings. The fire that burned the mid-rise wood framed apartments in Madison, Wis., last August was so hot that 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, a condition also experienced in the other major fires. 
 
Insurers have long been wise to these risks. "Wood” construction has a greater likelihood to burn or be damaged by fire and will be 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 pro-wood argument that it 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 the early word from some carriers is that they will adjust their premiums for wood frame construction in light of the major claims these fires represent. 
 
The risks associated with wood framing mid-rise buildings are obvious. Here are a few published comments from the fire in Los Angeles: 
 
"When you got that bare wood. It burns. It burns good,” said Capt. Steve Tufts, who oversaw a fire engine that responded to the blaze from an LAFD station on 51st Street in South Los Angeles. 
 
It burned especially well because the wood framing of the building "is probably the most flammable configuration of fuel you can have ... it’s like kindling.” —LAFD Battalion Chief David Perez. 
 
"You have a building that’s basically a pile of wooden sticks. When you get a fire going it’s going to take the whole building out. It’s like fighting a wildland fire: All you can do is slow it down until it runs out of fuel.” —John DeHaan, a veteran forensic fire scientist. 
 
Timber Time Bombs 
 
One of the arguments used by proponents of pro-wood code changes is that once the sprinklers and fire-mitigation systems are in place, wood framed buildings are as safe as concrete or steel structural systems. However, what happens when the gypsum wallboard used for fire protection assemblies is subjected to the normal structural strains and the wear and tear of occupants? And what happens when part of a building’s wood structure is exposed for months during renovation or repairs, including periods of time when adjacent units are occupied? 
 
The answer was provided in January with the inferno that destroyed the Edgewood apartment complex in New Jersey. Built in 2002, the four-story wood framed building had been constructed to code and with sprinklers for fire suppression. Twelve years after it was first occupied, maintenance workers who were doing a plumbing repair ignited the fire that rapidly spread inside the walls and ultimately throughout the building. The seven-alarm fire took 15 hours to contain. Fortunately, all the residents were able to escape unharmed. 
 
Two lawsuits have now been filed against the owner of the building, charging that the risk of fire during construction and for maintenance was known, and that risk is increased when using lightweight wood construction. One suit also cites statements made by Edgewater firefighters and other officials who "condemned the building’s ‘lightweight’ wood construction, which is cheap to build but more fire-prone than other accepted construction methods.” 
 
No one denies that combustible systems are extremely vulnerable during the construction phase, which can be lengthy, but the Edgewood fire points out that the risk of wood framed systems exists through to the end of the building’s serviceable life. And the recent jump in the number of mid-rise apartments, hotels and other similar structures should raise a serious question about whether today’s construction industry is planting timber time bombs that could easily go off tomorrow. All it takes is a match. 
 
Fortunately there are some elected officials who have taken note of what is happening in the real world of construction. LA City Councilman Robert Blumenfield is one of the first of our leaders to ask whether this is good policy for a safe community. Scott Rumana, New Jersey State Assemblyman, has upped the ante with his call for a halt on all multifamily developments in New Jersey until the state’s building code can be revised. Describing the Edgewater apartment building a "virtual tinderbox,” Rumana says that "the lightweight wood construction used to build the Edgewater complex is the reason the fire raced through the luxury apartment development so quickly.” 
 
Risks are part of everyday life, but the mounting evidence calls into question whether the initial costs savings from cheaper combustible construction is worth the risks. 
 

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