On August 29, 2007, Montreal-based architect Sevag Pogharian broke ground on Alstonvale Net Zero House, a project whose ambitious energy efficiency design earned it one of 12 berths in the 2007 edition of the Canada Mortgage and Housing Corporation’s EQuilibrium Sustainable Housing Demonstration Initiative program.
Pogharian, who founded the firm Sevag Pogharian Design in 1990 and eventually expanded its services to include not only residential design but construction, intended Alstonvale Net Zero House to embody extremely high standards of sustainability, energy efficiency, and comfort while still meeting a price target that would compare favorably to prices of other homes in Hudson, a prosperous community near Montreal. The house was designed to generate all the energy needed for its operation and for the household’s transportation needs, and it would feature home-scale agricultural components, including a greenhouse, to help feed the home’s occupants.
But on May 25, 2010, the nearly completed house burned almost to the ground. “I feel crushed,” Pogharian wrote that day in a blog entry on his firm’s website. His insurer is still investigating the incident, although Pogharian noted in a story recently published by the Hudson-St. Lazare Gazette that preliminary evidence points to combustion of polyurethane foam that had been applied in the attic earlier in the day.
Thinking through the possibilities
It was indeed a warm afternoon, reaching about 85 degrees Fahrenheit, when workers sprayed the polyurethane foam in the attic. The crew also ran a fan in the space to help ventilate it, although the fan was removed when the workers left at about 2:30 p.m. But if the foam in fact caused the fire, Pogharian observed, it’s unlikely its combustion was due solely to warm air in the attic. Instead, the lack of air circulation may have increased the concentration of combustible gases in the space, which could have caused the foam layer to thicken more than anticipated and further trap heat.
“I’ve come to learn a lot about polyurethane since the fire,” he told the paper. “It’s an exothermic reaction. You mix these chemicals, it gives off heat, and in the process it inflates. One of the things with polyurethane, if you apply it too thickly, the heat that is generated inside is not dissipated. It is an excellent insulation and it can combust.”
Pogharian’s initial responses to the disaster – depletion and inertia – changed for the better as time passed. He says he now is more motivated than ever to see the project to completion, pending settlement with the insurance company, which has already covered demolition expenses.
“I want to push this thing so it sees the light of day – the whole concept – the house, the car, the edible landscape, the net-zero greenhouse,” he told the Gazette. “I can walk away, or I can plunge in and try to get it done. If the insurance stuff gets worked out, there is no reason not to do it.”
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