Some 280 million pounds of spray polyurethane foam goes into U.S. houses every year, and by most accounts the overwhelming majority of those installations go off without a hitch. Tom Harris, an industry veteran and now a spray foam consultant, says homeowners lodge complaints less than one-tenth of 1% of the time—a better record than the auto industry.
Some builders have deep misgivings about spray foam’s chemical makeup, particularly the global warming potential of some of its ingredients. But spray foam also has a number of appealing characteristics: the ability to fill irregular voids in wall and ceiling cavities, highly effective air-sealing, and, in the case of closed-cell foam, high R-values and excellent vapor control.
Advocates love foam. Yet installations can go wrong and when they do, it can get ugly. Take this case from 2018, logged at Saferproducts.gov, a website maintained by the Consumer Products Safety Commission. A 37-year-old woman reported that spray foam had been applied in the attic to replace old batt insulation, and within a day of moving back into the house the family’s health began going downhill.
“We experienced adverse health reactions,” the unnamed woman wrote, “post-nasal drip, headache, anxiety, and upper respiratory symptoms. Since the day it was sprayed, our home has had obnoxious odor on the second floor. It is worse on hotter days. We had to abandon the second floor of our home and completely separate the air.”
The woman continued, “I contacted the manufacturer since we do not know what to do about our unsafe living conditions. The smell has not gone away and the contractor that installed it doesn’t think there is a problem or refuses to accept that the product is faulty.”
According to a response filed by the company that manufactured the chemical components, an…
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