Since 2009, large construction-site fires have destroyed 45 multifamily housing projects nationwide, according to a recent AvalonBay Communities’ press release. Most of those fires can be attributed to arson and cause developers large financial losses and potential worker deaths.
In response, developers such as AvalonBay (AVB), which recently received the International Risk Management Institute’s 2018 Gary E. Bird Horizon Award for the company's fire-suppression methods, are pioneering innovative methods to more safely and cost-effectively prevent or suppress construction fires.
Here, Jeffrey Hutchens, AVB's senior director of safety, shares how the firm’s loss-prevention program aims to eliminate construction-site fires at wood-frame projects.
Describe AvalonBay’s innovative fire-suppression methods.
Our program uses a combination of innovative building processes, including new technologies, and a novel wood treatment to eliminate structural fires in wood-frame buildings.
Although designed with wood-frame structures in mind, our approach has applications beyond wood-frame construction. And, while the program applies specifically to multifamily housing, it can eliminate fires in any structure constructed using wood, including single-family homes and structures with cross-laminated timber, mass timber, timber frame, and modular wood-frame construction.
What are the key pillars AvalonBay uses to help reduce and/or eliminate structural fires?
There are four:
1. Eliminate the need for traditional “hot works” and open flames on construction sites.
Although this might seem like an obvious solution, it's still a regular practice to use open flames on wood-frame construction sites. Examples of open flames, which have been eliminated on AvalonBay’s projects, include flame pots, salamanders, and open-flame heaters. We've also minimized the use of traditional hot works such as welding and brazing. Examples of specific changes in how we approach hot works include:
· Using only remote, forced-air heaters to heat and dry interior spaces in colder months; · In lieu of soldering, using crimp-style sealed plumbing connections;
· Replacing metal pipes with nonmetal pipes, where allowed by code;
· Bolting, not welding, stair connections;
· Prefabricating off-site any metal connections that need to be welded;
· If hot works or heating elements are absolutely necessary, using only certified trades and a strict, comprehensive hot works permit system.
2. Enhance site security.
Most construction sites lack basic security measures beyond a fence and warning signs. Temporary fencing is often moved or separated, to facilitate easy access to trailers or for deliveries, and never replaced. Often, anyone with a hardhat and work boots can take advantage of these multiple points of entry. Arson is known or suspected in over half of multifamily construction-site fires. Stopping unauthorized entry to the site after hours is essential to eliminating arson.
AVB enhances physical security by assessing the security risk at the site as part of the initial underwriting process. We use permanent or semi-permanent site fences where possible, with limited authorized entry points that are locked down at night. Construction projects in urban or “transit-oriented” locations or with difficult perimeter logistics have additional security measures identified. These can include smart-camera technology that identifies unauthorized entry and turnstile-access controls.
3. Promote early, reliable detection.
The classic method of detecting site fires is with a fire watch, but fire watches are subject to human error. Also, given the large footprint of wood-frame projects and the speed at which fire spreads, it's almost impossible for a fire watch to locate the source of the fire in time to limit its spread. Technology provides a much more reliable solution that enables very early detection of a fire.
We partnered with Pillar Technologies to provide a fully wireless and mobile multisensing environment inside our projects under construction. Pillar’s battery-powered detectors provide heat, humidity, volatile chemicals, and dust levels via a mesh WAN network. Project personnel receive text and email alerts if one of the preset alarm threshold levels is exceeded. The devices are fully mobile and easily relocated as construction progresses.
The presence of over 700 detectors on eight of AVB’s construction sites has enabled us to identify a temporary heater thermostat failure and two water-intrusion events. Our project teams and construction leaders can view the data stream from any of the Pillar detectors on Pillar’s website dashboard. Essentially, we get 24/7 project vital signs, with immediate notification at the inception of a fire or potential water-intrusion event.
4. Render wood fireproof.
Treating wood itself as a line of defense against fire isn't an innovation. Fire Retardant Treatment (FRT) and fire-retardant wood applications that enhance the fire-resistant qualities of wood have been in use for a long time. However, these processes and applications are time-consuming, expensive, and often use dangerous or toxic compounds. Most importantly, these products and applications may slow the spread of a fire, but they don’t eliminate the risk of fire.
We also partnered with start-up company M-Fire Suppression to use its innovative organic polymer wood treatment on all of AVB's wood-frame construction projects. M-Fire's Jobsite Spray is an easily applied surface treatment using environmentally safe chemistry. Wood products treated with M-Fire treatments won't allow the fire to utilize the oxygen in the wood. The effect is the wood isn't able to burn. Testing treated wood using ASTM flame-spread protocol resulted in essentially zero spread.
The M-Fire product meets California Proposition 65 notice requirements and achieved Underwriters Laboratories Greenguard Gold certification. It's also designed to provide protection for up to 10 years once the wood frame is protected from the environment with drywall; costs a good bit less than FRT; applies in seconds; is safe for workers, residents, and the environment; and won't affect the inherent structural integrity of wood. We worked with M-Fire to develop a process, plan, and logistics to apply the treatment in the field to maximize wood protection while minimizing impact to budget, schedule, and other trades.
How many properties utilize the program and where are they located?
Since launching the fire elimination program in 2017, we’ve protected each of our 14 wood-frame communities under construction. Over 2.5 million square feet have been treated with M-Fire’s organic polymer chemistry. Pillar has over 700 detectors monitoring our under-construction communities, which are located in Massachusetts, New York, New Jersey, Washington, and California.
Who are the key players in implementing the program?
Our construction professionals embraced the need to implement a new approach to protecting wood-frame construction sites from fire. From initial brainstorming to pilot, the process only took five months. Without the support of AVB’s 220 construction professionals, the fire-elimination program couldn't have moved throughout the organization as quickly.
M-Fire's and Pillar Technologies' principals were instrumental in shaping AVB's program. Both Steve Conboy (M-Fire) and Alex Schwarzkopf (Pillar) provided us with transparency regarding their respective product capabilities and limitations. Growing these two start-up organizations to capacity to support our wood-frame construction program was one example of the commitment they made to AVB’s successful implementation of our fire elimination program.
