Have all shingle manufacturers accepted unvented foam insulation of the roof deck in their warranty?
Zi98mPLYop
| Posted in Green Products and Materials on
I would like to use a foam insulation product in a 2 x 8 vaulted rafter space. Do I need to use baffles to circulate air under the shingles and thus not void the shingle warranty.
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Replies
No, "all" shingle manufacturers have not accepted unvented roof applications. You need to look at specific warranty info for the shingles you want to use.
Beth,
There are several related questions:
1. What does the manufacturer of your shingles have to say on this issue? You should research the answer to this question, since manufacturers have been flip-flopping on this issue.
2. Does a shingle warranty matter? There is a strong argument to support the contention that the answer to this question is No. By the time you submit a warranty claim, the amount of money you are likely to get -- a pro-rated amount for the remaining time on the materials only, with no labor covered -- isn't worth much. Moreover, shingle manufacturers have been known to decline claims due to minor installation errors (for example, misplaced fasteners). The hassle factor alone isn't worth the small check.
3. What do building scientists say? The answer to this question is, unvented roofs can work well, and many factors (most notably, shingle color) matter more than ventilation when it comes to keeping shingle temperatures low. If for some reason you are obsessed with keeping your shingles as cool as possible, then buy white shingles -- color matters more than ventilation.