Closed Cell Spray Foam insulation and hiring a contractor. - DIY Chatroom

Spud · 10-12-2009, 09:29 PM

Who makes the highest R-Value per inch of closed cell Spray Foam . What is the highest per inch that can be had?

Dow Corning Styrofoam SPF spray foam is R-6.6 per inch. Gaco Western has their spray foam at R-7 per inch.

Anyone know of a spray foam with higher than R-7?
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Code in my area is R-38 for vaulted ceiling. If I hired a contractor to spray foam, can he spray my desired inches even if the R-38 code isn't met?

Is he bound by law to only spray code required values or higher?

Thanks

PerpetuallyRepairing · 10-13-2009, 11:12 PM

The R value of all closed cell foams as far as I can tell is the same. I wouldn't worry about 10% differences in reported value. Supposedly the R value decreases with time. Perhaps that is the reason for differences.

I would strongly suggest sticking with code to prevent ice dams in your area.

ccarlisle · 10-14-2009, 11:03 AM

No, foamers aren't like, say plumbers or electricians. I am not sure of your codes where you are but up here some code violations have to be corrected where they impact on safety for example, an electrician has to rewire a plug if that plug is not currently up to code and regardless if the HO asked him to or not (I mean he couldn't just put a plug on bad wiring). But in the case of a foamer, I say that the code is a minimum guideline and not considered violated if not met. The foamer will spray whatever you want so if R38 can't be met in the space provided, he'll do what he can.

Inspectors have enough to do without being a Big Brother. "Live in ND and want R12 in your ceiling, do ya?"