Understanding Roof Underlayment and Ice-and-Water Shield
Most homeowners judge a roof by what they can see: the shingles or metal panels on top. But the material that does the quiet, unglamorous work of keeping water out of your house is often the layer you never look at. Underlayment sits between the roof deck and the finish surface, and on a rainy island roof it can be the difference between a dry attic and a slow, hidden leak. In San Juan County, where roughly 40 inches of rain falls every year and November storms drive water