The roof underlayment is actually a layer put between the sheathing and shingles. It’s an extra humidity barrier that protects your roof decking from h2o that can be put under the shingles. The underlayment is available in the 3 types mentioned beneath: Not all roofs require drip edges and ice https://eduardoimqux.hazeronwiki.com/7204712/roof_fix_fundamentals_explained