We have a 22 year old home located in southeastern georgia where the humidity is very high. In the past 2 weeks our floors have started buckling all over. We have a vented crawl space and the old insulation is drooping from moisture and the wood is wet. We are debating between the "encapulation" method or the spray foam method to repair this issue. Which would you recommend? https://youtube.com/watch?v=ggLAUsiuI_o
Global warming potential (GWP), as defined by the EPA, is a measure of how much energy the emissions of 1 ton of a gas will absorb over a given period of time, relative to the emissions of 1 ton of carbon dioxide (CO2). Spray foam insulation products that use water as the blowing agent - typically open-cell foam however Icynene’s ProSeal Eco is a 100 percent water blown closed-cell spray foam – have a global warming potential of 1, the lowest possible number. This is because water in the mixture reacts during the application process to release carbon dioxide and heat. The GWP of the blowing agent is that of carbon dioxide. Carbon dioxide has a GWP of 1.
As this example illustrates, it's important to seal the envelope completely. One of spray foam's biggest selling points is its air-sealing ability, but it can't seal places where it's not sprayed. One of the nice things about using spray foam in new construction is that you can do a Blower Door test before the drywall goes in. Even better, you can test for leaks with a fog machine. http://m.youtu.be/ggLAUsiuI_o
Jennifer, I'm not an expert on the health effects of closed cell foam. A lot of people live in houses with closed cell foam and have no health problems from it, at least not short-term, acute problems. I do know of one person who had it removed from her crawl space because she was convinced it caused her dog to get sick, but I know only what she told me.
Starting a new build (1 1/2 basement walkout), all 2x6 exterior walls w/ brick veneer in CZ3. Above grade, would like to do spray foam in 2x6 walls, 1/2" or 1" of rigid foam board on the exterior, and a 1" air gap. Will this require a house wrap or can I do w/o the rigid foam and go with a housewrap? Also, any recommendations about insulation strategies for the finished basement. Thanks!