a) What is the proper term for the “glue” on the back of roofing shingles?
b) When laying a new roof over an existing roof, is it correct that the protective plastic film over this “glue” remains in place (sometimes) so that the nails have extra material to grip?
If you have an answer for (b), please elaborate on when this is the correct thing to do.
Thanks,
This guy calls it “roofing cement”, the same link has a question/answer about laying a new roof over an existing roof which may address your (b). If not, I guess you could drop a specific question to the site.
WARNING the site is hosted by the Boston Globe, don’t tell Cecil.
This is a fairly comprehensive guide to installing shingles (PDF document). I don’t see the situation you’re referring to.
Do you mean the roofing cement on the face of the shingle, just above the tabs?
That’s there to hold the tabs of the row above it down, if that’s the plastic strip you mean, you always remove it (it’s applied at the factory right after the cement is, to keep the shingles from getting glued together!).
CMC fnord!
Sorry, no need to remove the plastic strip. It’s there to keep the shingles from sticking together in the package. When the shingles are applied on the roof with the correct exposure the plastic does not line up with the sealant anymore. It’s doesn’t hurt to remove it, it’s just wasted effort and something else to dispose of.
What ever you do don’t step back to admire your work.