Most closed-cell spray foam is now formed using hydrofluorocarbon (HFC) blowing agents that have high global warming potential, partially or completely offsetting the climate benefits of the energy savings they can offer. In the United States, HFCs are scheduled to be phased out by January, 2021. A few spray foam suppliers have started supplying spray foam blown with hydrofluoroolefin (HFO) blowing agents without this problem as of early 2017.[14]

Thank you, Allison. We have a split system unit (actually 5) with the heat being propane. The foam guy said that it needed ventilation, so completely sealing the attic wouldn't be a good idea. It sounds like you are saying that the systems need to be vented out of the attic or replaced with some type of closed system. But I shouldn't bother spraying if the plan is to leave the soffet vents open. Is that correct?
I am on my third project with foam it green. I like the simplicity of it, the color blending to make it green, it alerts you quickly if something is wrong with the blending so you don't waste alot of valuable material. Follow the instructions closely, put in the prep time and you will have no issues. It seems most people's negative comments have to do with not following instructions or guidelines. It is about as close to point and shoot as you can get but there are still some essential details that need attention. The only complaint I have is the fragility of the gun, last project I cracked one on accident but luckily needed two kits to finish the project so I had a back up, but I was more careful to gently lay the gun down between applications.
Current guidelines recommend up to 10 inches of insulation in your attic . This is usually added to the ground, rather than the roof line, which results in the loss of your storage area, due to not being able to refit floor boards after installation. By implementing spray foam insulation to the roof line, you regain the lost 10 inches, thus increasing storage, height and practicality.
Sealection® 500 has been Demilec's flagship product for more than 20 years, and has positioned Demilec as an industry-leading spray foam insulation manufacturer. As an environmentally-friendly product, it delivers superior performance, energy savings, and is an excellent return on investment for architects, builders, contractors, and homeowners, making it the ideal choice for insulation.
If your foam pulled away just a little bit, Jamie, and they were able to fix it with just a little bit of touching up, then it wasn't as bad as the house where I saw this problem. As the last photo above shows, it had pulled away significantly from the studs and rafters, and it was all over the house. This was closed cell foam, and interestingly, it didn't pull away from the horizontal framing members, just the vertical and sloped ones. They did some touch up, but that wasn't enough. I don't know how this one ended up getting resolved. I think maybe the contractor came back and sprayed cellulose on top of the foam.

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