Rainy Roofing: Why The Felt Can Be Wet

Roofing felt is used as a base over wood rafters and then shingles are laid upon it. The National Roofing Contractors Association (NRCA) includes roofing felt in its recommendations for roofing and waterproofing. Building codes also commonly require this material as a layer between the roof deck and shingles. Here are some things you may be wondering about roofing felt.

Purpose of Roof Felt

Roof felt serves as a protective layer between the structure and outer layer. It helps protect against water entering the building. First by absorbing the water, then releasing it. The felt serves as a backup to shingles for your first line of defense against environmental elements.

Materials Used in Roofing Felt

This tar paper is rolled on a deck like paper and serves as an underlayment layer. The base is made from either natural materials such as wood cellulose or synthetic materials such as polyester. A protective water repellent coating such as asphalt is then applied.

When Roof Felt Gets Wet

The felt is actually what keeps your roof dry! The shingles are in place to protect the felt. The felt can get wet. However, due to its water repellent properties, it acts more as a shield than a sponge. The felt collects and then repels the water, allowing the roof to breathe.

Felt will often get wet with a Cedar shake roof since this type of roof is designed to soak up then shed water.

Roofing felt should ideally be dry when shingles are installed to avoid ripping, but it’s still possible to install when wet. The felt can be damaged if exposed to moisture too long.

Other Advantages

Roof felt gives your roof a better appearance and will help it last longer.  The felt helps ensure water drains off the roof after a storm. It helps keep your roof free from moisture, which can lead to leaks, rot, and mold. The felt also serves as a protective membrane against ice or snow dams.

Give your next roof extra protection with roofing felt, which adds a layer to help keep water away from your structure. Contact us at Midwest Roofing, Siding & Windows Inc. to learn more about what you need for residential roofing.

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