Massachusetts Fires Tied to Spray Foam Incite Debate
As an insulation product, spray polyurethane foam (SPF) has many great attributes that we've talked about on this website: easy installation in irregular locations, air barrier qualities, and moisture management potential. Our publications and blog have also been active in covering some of the downsides of this product, including toxic emissions for workers and occupants under investigation by the EPA and the high global-warming potential of SPF. We have also been publishing a series of reflections by a builder who strongly favors more natural, breathable materials like cellulose.
But when SPF is implicated in building fires, it really turns my head! We're talking not about more vague, statistical likelihoods of future risks--we are talking about lives and property being endangered or lost in the moment. We wrote about that last year in the context of an effort by a fire marshals group to get the word out about unique fire risks from green building. That article referred to the tragic fire at the Alstonvale Net Zero House in Hudson, Québec, which occurred immediately after SPF installation, and reduced an almost-completed home to rubble.
Now the heat is on again: as our friend Martin Holladay at GreenBuildingAdvisor.com has written, three Massachusetts home fires have been linked to SPF installation:
The Massachusetts Division of Fire Safety (DFS) is investigating the causes of three house fires that were ignited while insulation contractors were installing spray polyurethane foam. According to Tim Rodrique, the director of the DFS, investigators suspect that the fires were caused by the exothermic reaction that results from the mixing of the two chemicals used to make spray foam.
One of the fires destroyed a $5 million home on the exclusive Penzance Point peninsula in Woods Hole on February 10, 2011.
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The house was being renovated at the time. According to the Cape Cod Times, "firefighters were somewhat stymied due to spray-on foam insulation. ... Similar insulation has proven deadly in the past. In 2008, Robert Cowhey of Springfield was spraying soy-based foam insulation in the attic of a North Falmouth home. The chemicals were located in a truck outside the home in two 50-gallon tanks, but somehow they ignited and Cowhey died in the ensuing fire."
Robert Cowhey, the victim who died in the North Falmouth fire, worked for Green Mountain Insulation of White River Junction, Vermont. Cowhey was installing SoyTherm50 spray foam insulation when the fire broke out.
When SPF is being installed, an exothermic (heat-producing) chemical reaction occurs. That reaction continues for some hours after installation is complete. If this heat doesn't have a way to escape from the foam, there is a risk that the foam could spontaneously combust. Foam contractors manage this risk primarily by limiting the thickness of SPF that is installed in one pass, to about two inches. In hot, stuffy attics, ventilation with fans may also play a role--or at least the absence of ventilation may have played a role in the Alstonvale fire. Holladay's article goes on to note:
On July 1, 2011, Stephen D. Coan, the Massachusetts State Fire Marshal, issued a memorandum to the heads of every fire department in the state. The memo notes, "Recently, the Department of Fire Services, Division of Fire Safety, has become aware of a number of fires involving commercially available spray-on foam insulation. At least 3 fires, one being a fatal fire, are believed to have been started during the application of spray foam insulation, and currently remain under investigation. ...
"Information gathered by the Division of Fire Safety from different manufacturers indicate that there are several possible scenarios that could lead to a heat build-up, and a possible fire scenario. These are: improper application techniques (excessive thickness, or spraying new material into the already applied rising foam) and/or improper mixtures of the chemicals at the application nozzle.
"Based upon this information, the Division of Fire Safety is recommending that you work with your building officials to determine if such applications are taking place within your community and, if so, to also make contractors in your communities aware of this potential fire hazard and encourage that they follow application instructions accurately."
The many comments on this article produce both light and heat at times. Paul Dion writes:
Let us all not all go off the deep end here and make spray foam the green industry punching bag. This case again speaks to error in the installation process. Sprayed in place foam when used in accordance to factory standards by trained applicators that care, is safe. I see the potential however for more of this bad press for foam as a new generation of not so committed foam applicators are buying equipment and doing things with spray foam that should not be done. This is an emerging building product in our industry and is growing faster in popularity than it can be regulated.
Sevag Pogharian, the architect and owner of the Alstonvale house, apparently has turned against SPF since that fire:
Homeowners and architects are seduced by the R-value of high-density polyurethane without sufficiently understanding or considering the risks associated with this product. As an architect and developer, I paid a very high price for this seduction.
Pogharian goes on to note reasons that we should avoid SPF. Several commenters, including Andrew Cole, take the other position:
In Canada, we install millions of kilograms of spray foam a year. As a member of CUFCA we track our work on daily worksheets that are submitted to our association. We have a great Site Quality Assurance Program that involves site testing, and recording on each and every job. The occurrences of fires directly linked to foam are few and far between and those that do occur, are usually traceable to operator error. I am not saying that this is acceptable. Clearly our industry has to do more to educate installers. But we also need a process aligned with inspectors to get the unqualified people out of the business. As in any industry we will always have issues surrounding competency. There are very good, very competent contractors and there are those that are not. But to discredit all of the good that 2lb. Closed Cell SPF can do due is really not acceptable. Plane crashes are a horrific tragedy, yet we continue to fly.
What do you think? Have you installed, spec'd, or been in a building using SPF? What was your experience?
Photo credit: Dave Curran Caption: Fire investigators suspect that a fire that destroyed a $5 million home in Woods Hole, Massachusetts, was ignited in connection with a SPF installation process.
Published July 14, 2011