Peel-and-stick roofing underlayment
joenorm
| Posted in General Questions on
What is the appropriate assembly to use an essentially vapor closed peel and stick roofing underlayment?
If the assembly is vented is this OK? I read a lot of talk about potential moisture traps and rot associated with these products.
thanks
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Replies
Joe,
Peel-and-stick roofing underlayment should be used sparingly, and only where necessary. This type of product is sometimes code-mandated in cold climates (usually at the eaves and at valleys, as a desperate attempt to prevent damage to roofs and walls due to ice dams). Note that there are better ways to prevent ice dams than the liberal use of peel-and-stick.
If you are building a well-designed vented roof assembly, the appropriate use of peel-and-stick products won't trap moisture. But in most cases, you don't need it everywhere. Use it where necessary.