Home Forums Spray Foam Insulation What type of spray foam insulation is best for subfloors and/or crawl spaces? Reply To: What type of spray foam insulation is best for subfloors and/or crawl spaces?

Green Apple Insulation
Keymaster
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Your situation is very common, a large majority of homes in the New Orleans area were in fact built with this style of subfloor for the simple fact to allow air flow to circulate throughout the home during the hotter months of the year. This was a great idea when we depended on the outside elements to keep our homes cool in the summer, but now with central heating and cooling we have to retrofit our homes to work properly with this new technology.

So there is a lot of controversy with open and closed cell spray foams when it comes to subfloors. In the early years when spray foam was commercialized for residential application it was a learning curve for most companies getting into the business. So there was mistakes to be made.

So to answer your question, 2 inches of closed cell foam would be the best option for your particular situation. It will seal the entire underside of your home, and provide a total of about R16 of insulation value to the underside of the home. So no more drafts and no more cold feet. Also I’d like to add that sealing up those cracks and gaps will help prevent those unwanted insects and bugs out of your home as well.