3 Roofing Underlayment Options for Utah Homes

Before shingles are attached, roofing underlayment must be secured in place over the roof deck.

Underlayment is a layer of material placed over the bare wood decking that works as a water barrier, preventing moisture from seeping in and causing damage to your roof or the inside of your home. It also helps your shingles lay flatter, allowing for a smoother, more uniform appearance and a longer life for your roof.


When it comes to selecting an underlayment, advice from a professional roofing contractor is recommended. But to understand your options, it may help to become familiar with the three most common types of roof underlayment materials.

1. Asphalt-Saturated Felt Roofing Underlayment

Black felt paper saturated with asphalt is commonly used in home roofing projects throughout Utah, as it is more cost-effective than other underlayment materials.

Asphalt-saturated felt often has an organic cellulose base, though it may also be made from fiberglass substrate. This material is available in 15-pound and 30-pound rolls. The heavier felt is thicker and stiffer, which makes it more resistant to the elements than the 15-pound option.

2. Rubberized Asphalt Roofing Underlayment

Rubber-like materials are also frequently used for underlayment throughout Utah. Referred to as rubberized asphalt, this option is manufactured to improve moisture resistance and prevent heat damage to the roof decking.

Roof underlayment made of rubberized asphalt is self-adhesive, unlike black paper felt. Consequently, this material seals well around fasteners like nails and staples. Some types also have a polymer film bonded to the surface to further prevent damage and deterioration.

In the future, asphalt-based underlayments may be used less often in Utah homes. Many manufacturers have begun to phase out these materials because the crude oil industry is producing less asphalt.

3. Non-Bitumen Synthetic Roofing Underlayment

Polypropylene and polyethylene — the same synthetic polymers used to create textiles, food storage containers, plastic bags and countless other everyday objects — are also used to make roofing underlayment.

Non-bitumen (or asphalt-free) synthetic underlayment is lightweight and strong. Plus, since the material doesn’t absorb moisture, it is quite resistant to fungal growth and may work better to prevent water and heat damage to your roof decking.

That said, non-bitumen roof underlayment products are more expensive than other options. And some synthetic materials may not meet building code or manufacturer warranty requirements.

So which underlayment material is the right choice for you?

That’s a question best answered by a professional roofing contractor. Knockout Roofing of Utah has been providing quality roof installations for over 15 years. Our team has the knowledge and experience you want on your side.

For a complimentary consultation and estimate, contact our Salt Lake City office today.