What is the Purpose of Roof Felting?

Posted on: January 29, 2018

While gathering info about your next roof installation, you may be wondering whether roof felting is a necessary step. You could attach shingles directly to the plywood wood roof deck, so why add another layer?

Roof felting provides an important protective layer to your roofing system, but it also makes the job safer for installers and improves the looks of your roof when everything is finished.

What Is Roof Felting?

Products referred to as roof felt or felt underlayment can be made of cellulose fibers or polyesters infused with asphalt. There are also tar paper products, and sometimes people call roof felt “tar paper” regardless of the material.

Roof felt products are sold in rolls. An adhesive side sticks to the roof deck or a waterproof membrane on top of the deck. The outer surface of the roof felt is like a sandpaper or carpet-like surface. Shingles or shake can be nailed directly on top of the felt.

Benefits of Roof Felt

Roof felt products were first invented to protect a home’s roof deck from rain during construction or roof replacement. Installation also goes much more smoothly with roof felt, because it’s safer to stand on than a plain plywood deck—especially for steep-sloped roofs.

After roof installation, roof felting provides many other benefits:

  • Moisture protection. Although roof felting is never 100% waterproof, it does help absorb and wick away some excess moisture. Without felt, it’s more likely that your attic insulation will get mildew or that the waterproof membrane will fail sooner.
  • Fire protection. Felting increases the fire safety rating of a roof system. It’s possible to achieve a Class A fire rating even if your preferred shingles are Class B, by adding quality roof felt.
  • Aesthetics. The rectangular lines of the wood panels below your roof’s shingles can sometimes show through over time. Felt smooths out the surface so your roofing looks more uniform.

In short, think of roof felting as a foolproof way to increase the longevity and performance of your Baltimore roof!

Roof Felting and Waterproof Membranes

Worried about moisture damage to the home? Roof waterproofing protects your attic insulation, exterior, foundation, and the rest of your home from mold and water damage.

You could add only the waterproof membrane to the roof deck, but then you’d be missing out on all the other benefits of a proper roof underlayment. The best roofing system consists of wood decking, a tight waterproof barrier, roof felt, and your choice of shingles, shake, or metal roofing.

Roofing Repair & Replacement in Baltimore

If you’ve already struggled with a leaky roof or you simply want the best roof replacement, talk to the best roofers in Baltimore! Park Heights Roofing can repair your roof or conduct a full re-roofing with the perfect roof felting products for your house in particular.

Contact us online or give us a call at (410) 358-1257 to request an inspection or estimate for roofing services in the Baltimore area.