Felt Roofing
Roofing felt is the base material (underlayment) put down over the plywood panels on a roof. Despite the name “felt,” it’s not the felt you think of as felt. Roofing felt is made from either wood cellulose or fiberglass that is coated with a protective layer of bitumen (asphalt) to repel water that gets underneath shingles while still allowing the material to “breathe.”
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