R-38 ceiling and spray foam
jackofalltrades777
| Posted in Building Code Questions on
If one sprayed 5″ of open cell spray foam on a ceiling area, that would equal to around R-17.5, correct?
Now code requires R-38 minimum for the ceiling in this area. There is no “performance value” of R-38 in 5 inches of open cell spray foam, right?
That would be a marketing line bunch of nonsense as 5″ of open cell is R-18 avg. and anyone claiming it is performing like R-38 is lying. How would the code department buy into this nonsense?
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Replies
Peter L.,
Energy experts have been bemoaning the misleading marketing efforts of spray foam manufacturers and installers for many years. Here is a link to my 2010 article on the topic: It’s OK to Skimp On Insulation, Icynene Says.
Martin,
Thanks for the article. WOW! That is exactly the lie the spray foam company is telling the homeowner. That 5.5" of open cell foam "performs like R-38" when we truly know that it is basically an R-19 ceiling and NOT R-38.
This is a travesty that a new home will only have an R-19 ceiling when it requires an R-38 ceiling and the spray foam company pulled a quick one on them and the code department.
I bet the homeowner will feel it via their pocketbook when they get their heating and cooling bills. An R-19 ceiling in 2015 when it calls for a minimum R-38 is completely ridiculous.
What about reporting the spray foam company to the FTC?
Peter,
I have been reporting marketers who are not complying with the Federal R-Value Rule to the FTC for many years. Unfortunately, my efforts have not resulted in a discernible uptick in enforcement actions by the FTC. But I urge GBA readers to keep sending those letters and e-mails to the FTC anyway.