Roofing underlayment is what lies between the shingles and the roof sheathing, or roof deck, which is typically either plywood or osb. It’s installed directly on the roof deck and provides a secondary layer of protection from the elements, including rain, snow, and wind.
What Is Under Shingles on a Roof?
Underneath your shingles is a critical layer of your roofing system known as the underlayment. The underlayment is a water–resistant or waterproof barrier that is installed over your roof deck.
It is designed to protect your home from water damage that can occur when your shingles are damaged or blown off in a severe storm. While the underlayment is an important part of your roof, it is not visible from the ground.
This layer is usually made of felt paper or a synthetic material, and it is installed between the roof deck and the shingles.
The underlayment is often referred to as the “roofing felt.” The underlayment is an important part of your roof because it provides an additional layer of protection against water damage.
If your shingles are blown off in a severe storm, the underlayment will prevent water from entering your home through the roof deck.
The underlayment is also important because it provides a barrier against wind–driven rain. Wind–driven rain can enter your home through gaps in your shingles and cause water damage.
The underlayment will prevent wind–driven rain from entering your home and causing damage. The underlayment is