Underlayment Talk: Park City Roofer Explains No. 15 and No. 30 Underlayment
The underlayment is the layer beneath your roof that provides a second line of defense against the elements. Today’s underlayment materials are made out of polyester or fiberglass, replacing the asphalt-saturated housewrap-like felt that was commonly used in homes before the 21st century. Under the International Residential Building Code, asphalt shingles are required to have an underlayment. A Park City roofing contractor offers two kinds of underlayment materials, No. 15 and No. 30 felt. You can immediately spot the difference between the two: No. 30 underlayment is thicker and more rigid than the No. 15. Normally, the No. 30 underlayment… Read More