Roofing experts agree that the installation of a shingle roof deck underlayment is essential to a long-lasting, leak-proof roof system. Why install a tile roof protection? This is why. The roof deck protection serves as secondary protection against water spillage in the event of a roof leak. Shingle protection, roof deck underlayment keeps wood resins away from shingles. Some resins can damage shingles, so be careful what touches the shingles. The deck leveler, shingle roof protection helps create a flat, even deck surface. Breathable layer that helps prevent interior moisture from being trapped within the roofing system itself. Finally, roof deck protection is needed to obtain a UL Class A fire resistance rating on shingles. The reason you need breathable roof underlayment protection that goes under shingles is to make sure your roof breathes to reduce excess moisture and ensure maximum protection from heavy rain and high winds.

Today’s modern houses are built to be weatherproof, so common moisture forms when cooking, bathing, cleaning, etc. has less chance of escaping. Using non-breathable roof protection on the deck can create a barrier that traps damaging moisture within your roofing system. Over a period of time, this can cause roof rot, mold, mildew, and costly structural decay. Many homeowners are unaware that moisture can travel by turning into vapor, moisture can travel through ceilings, once it is in the air, and will migrate through ceilings using natural convection. Moisture stops at the first waterproof barrier, in this case, the non-breathable roof deck protection. Moisture condenses between the roof and deck, changes from vapor to water, and can then settle between the deck and the non-breathable subfloor of the roof deck.

When there is trapped moisture, your roof protection doesn’t breathe, it can trap moisture between the top of the roof deck and the bottom of the roof protection. Hazards from trapped moisture can include plywood delaminating and rotting, OSB expanding and rotting, structural framing warping and rotting, shingles blowing off, roofing nails rust and lose their ability to hold shingles in place. There are some synthetic protective roof coverings that do not breathe. Their very composition does not allow moisture to pass through them. Made with plastic/polymers, these products are not the asphalt roll roofs many people may think of when they hear the term roof deck protection.

The reasons for using a roof deck underlayment is because there is less sag in the roof due to its fiberglass construction. It can be straightened by sunlight, if it doesn’t wrinkle. It acts as a vent so that moisture from the attic can breathe through it.