Your roof is made of more than shingles and gutters. So what’s underneath your shingles? Only the support system for the rest of your roof! Roof sheathing strengthens your roof so it can protect your home. Let’s take a minute to talk about what roof sheathing is and what it does.

What is Roof Sheathing?

Roof sheathing, also knowns as decking, is an important layer of wood. It strengthens and supports the rest of your roof. Decking is made of either plywood or OSB (oriented strand board) and attaches to the trusses and joints on the roof. The roofer attaches the shingles to these squares or planks of wood.

What Does Roof Sheathing Do?

While the decking’s primary purpose is to strengthen and offer roof support, here are few additional benefits.

Helps Stop Leaks

Roof sheathing helps to stop leaks. Many years ago when asphalt roofs were used, roof sheathing wasn’t always installed. What homeowners discovered is that their roofs were more likely to leak. Today, most shingles feature a number of weatherproofing treatments. However, the extra layer provides another layer of protection against the elements. Since many decking boards are also weatherproofed, your roof is well-protected prolonging the lifespan of your roof and safe from water damage.

Strengthens & Supports Your Roof

Sheathing helps evenly distribute the weight from asphalt shingles, snow, or rain and ensures that they don’t cause sagging or bowing.

Provides Fire Protection

Finally, sheathing can also help prevent fires. Nothing is 100% fireproof. However, many decking materials come treated with fire retardants that can help resist fires on the roof or attic.

Do I Need New Roof Sheathing?

Roof decking is an important component of your roofing system. The most common reason to replace it is that the sheathing is old, outdated, damaged, or installing a new roof. But there are a few other signs. Its time to replace your decking if you

  • Can see broken sheathing boards
  • Have bad water damage on any part of your roof
  • It’s starting to rot in places
  • See light passing through holes in the roof
  • Notice the ceiling or roofline sagging

Roof sheathing is a very important part of your roof. If it’s damaged or leaking, it needs to be fixed.

Is Plywood or OSB Decking Better?

Both OSB (oriented strand board) and plywood are made of wood. However, OSB is more lightweight and costs slightly less. Plywood is a bit heavier and costs a bit more. Many roofers use OSB unless working with heavier materials such as slate or concrete roofing tiles. Plywood is usually a better option with these roofing materials.

It’s a good idea to inspect your roof at least once a year. Call a Perry Roofing Company if you need help checking the roof, don’t want to climb on the roof, find some suspicious areas, or have any questions. We are here to help. 479.306.4327