In renovating an old house, is spray foam insulation the way to go? And which type of spray foam insulation - open cell or closed cell?
Joanne Ciccarello/Staff/The Christian Science Monitor
Want to get confused? Listen to several contractors tell you the best way to insulate your drafty old house.
That’s exactly what I did last week. And after puzzling over how people could come to such widely varying conclusions, I have now emerged from the experience better versed on spray foam technology than I ever thought possible – and am almost, but not quite, ready to make a decision.
Early on I opted against traditional fiberglass batting (pink or yellow) because, from my earliest research, I thought that it was clearly not the best choice for us, even though it’s the least expensive in the short term.
The primary reason has to do with our decision to put in geothermal heating. For it to work optimally, a house has to be as airtight and insulated as possible. With a 1902 farmhouse with plenty of nooks, crannies and cracks, fiberglass batting just won’t do the trick, according to the various experts I spoke with.
So we knew we wanted to put in spray foam insulation – and a good, green spray foam at that.
“Spray foam gives you an air barrier which is our secret weapon – it doesn’t allow for any air movement like fibrous insulations,” says Ned Williams of Connecticut Spray Foam Industries in East Haven, Conn. “Air infiltration is really becoming enemy No. 1 in the insulation battle, while R-value is turning out not to be the simple savior.”
OK, once we decided to use foam to seal up our leaky house, the next question was whether to choose open-cell or closed-cell foam?