Insulation

[mjdeutsch]

John,

I am building a new house, I know you have used spray foam insulation on your shop project. I am getting different stories depending on which insulation contractor I talk to. the contractor my builder usually uses is proposing a 1" layer of 2 pound foam to achieve the sealing and then useing blown cellulose to achieve the higher R values. I am interested in the 1/2 pound foam that fills the whole cavity, but its R values are lower, which scares my builder. An insulation contractor I contacted on my own had alot of bad things to say about the 2 pound foam, saying that it will off gas which is not good for your health, crack, which would break the seal, and if your roof leaks, it would hold the water against the wood promoting rot and mold. Here is the kicker, the blown cellulos only that the builder usually uses is $5,000, the 2 pound foam w/ blown cellulous is $6,000, and the 1/2 pound foam is $15,000. What kind of foam did you use? Are you happy with it? how thick is it? Is R value critical or does the sealing aspect offer the bigger advantage? FYI I live in Indianapolis, IN so our winters are not as cold as yours....or as good of riding. LOL

Thanks a bunch, read your journal every week, keep living the dream!!

Mike

 

[jd]

I used this stuff. Tiger Foam

I used the slow rise stuff, which gave me an R-7 per inch. That is a higher rating than you are going to get with any other type of insulation out there (to my knowledge anyway).

A lot of what the one contractor is telling you just does not add up. First, once the foam cures (about 10 minutes) there is no more off gassing. Plus, any roof that leaks is going to cause major problems with wood rot and insulation damage- no matter what insulation you use. I would tell that contractor that is why you build a roof right the first time and not have to deal with roof leaks.

Most of what I insulated is behind wall material, but there are a few spots that are still visible and there is no cracking what so ever, so I am not sure what he is talking about there either, unless other types of spray in crack.

I'm not saying that this is the best solution for you, but I am very impressed by it. Gives a good tight seal, gives me an R-40+ in my 6" walls and I never have to worry about things like settling like you do with blown in cellulose. I was able to do it myself, so I saved a bundle on labor. I only wish I had done the cabin walls with this stuff!

-John