What is Roofing Felt and Why is it Important?

You don’t have to be a contractor to know that your roof is an integral part of your home.  Making sure that your roof is on par for its lifetime is part of keeping up with its due maintenance, and you may have heard of something called roofing felt while investigating its protection.

What is Roofing Felt?

Roofing felt, sometimes referred to as tar paper, lines the roof between your house and the final layer of roofing material.  Simply put, it’s an extra layer of protection from the outer elements. If you live in a damp climate, like the Pacific Northwest, a coastal climate with plenty of testy weather conditions, or in the Midwest, where snow blankets the region—and roofs—then installing roofing felt isn’t a bad idea.

Roofing felt is sold in large rolls, typically 36-inches wide.  It’s comprised of fiberglass fleece or polyester that’s soaked and treated with a waterproofing agent.  Sitting snug between the final layer of your roof and your home, roofing felt provides a cushy barrier for wood sheathing from heavy layers of snow and ferocious downpours of rain.

Types of Roofing Underlay and Roof Felt Sizes

There are three main types of roofing underlay: asphalt-saturated felt, non-bitumen synthetic underlayment (known shorthand as synthetic underlayment), and rubberized asphalt underlayment.  There are also two different sizes of roof felt: #15 and #30, the main difference between the two being strength.

#30 roof felt is stronger, which for your home, means a lengthier lifespan throughout the arduous and often times abusive building process.  #15 roofing felt is more likely to tear as it is not as durable as its #30 counterpart, especially with workers treading across your roof during the installation process in heavy work boots.

The longer your roof is exposed to the weather during its reconstruction and the more time it takes to finish the roof, then you should consider #30 roofing felt as opposed to the not as durable #15.  However, if your roof is just going to take a day instead of a long-winded job of three weeks, and you aren’t in a climate zone that calls for much rain or heavy storms, then your roof can easily get by with #15, saving you a couple of bucks.

Why is Roofing Felt Important?

At this point, you already know that roofing felt is what helps keep your roof waterproofed, resistant to adverse weather, humid climates, and steady streams of storms or snowfall. In spite of this, there are other reasons to include roofing felt in your roof’s underlayment.

Roofing felt fills out the line of defense when shingles cannot.  While shingles reflect UV rays and are the first to meet bad storms head on, they aren’t always sealed at all corners and a strong wind can cause them to blow right off.

Of course, during a big storm that blows through, homeowners aren’t out there right away to install new shingles.  It could be a few days or weeks before you or a professional is able to get up on the roof for repairs.  Roofing felt is there for back up, ensuring that no moisture will penetrate through your home.

The same idea goes for when your new roof is being installed.  The roofing felt protects the roof deck from rain if your roof cannot be installed in a day and there happens to be some bad weather passing overhead.  Protection doesn’t just stop at the elements, either.

Roofing Felt Protection

Roofing felt also protects your roof from resins that bleed out of the sheathing, and in case of fire, the layer of felt serves as an additional barrier to slow down burning.  For some houses, the layer of felt can also help smooth out roof sheathing, preventing unevenness from appearing in the final layer of shingles.

You may not consider this, but roofing felt actually creates a safer working environment for your roofers.  The roofing felt is useful because while workers are replacing shingles, fixing damages, or replacing the roof entirely, the felt has a gripping surface that minimizes their chances of slipping and falling. The last thing any homeowner wants is a poor roofer to fall on the job, and worse, be legally responsible for the damages.

Homeowners know how big of a role moisture plays in the integrity of every part of their home and its structure.  When moisture sneaks in, even through the roof, it can rack up hundreds of dollars in damages by weakening the structure, inciting mold and mildew growth, and warping wood or staining the walls.  And that alone should be enough of a reason to include roofing felt in your roof replacement.

The Argument for Roofing Felt

You may hear a few words saying that roofing felt isn’t entirely necessary, but consider the small cost to install this additional, protective barrier beneath your final roof that can extend its longevity among other advantages.  Roofing felt is but a small price to pay to add another layer of moisture-repelling underlayment for your home.

What About a New Roof?

A roof normally lasts up to 20 years but it can be shorter if you live in the Midwest. You can extend the life of your roof by doing some yearly maintenance but don’t wait too long because a depreciated roof can cost you on monthly energy bills. In fact, a new roof can drastically improve your home curb appeal as well as energy efficiency.

At Feldco Roofing, we have several asphalt shingle styles and colors to match your home. In addition, you’ll have outstanding protection from weather elements thanks to triple layer protection and adhesive power shingles. Speak to a specialist and get a free quote online today.

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