How to Choose Underlayment for My New Metal Roof?

Are you ever wondering how to choose underlayment for my new metal roof? Republic Roofing is here to help. While metal roofing has become a popular roofing option among both homeowners and commercial property owners in the United States, to get the best out of your investment, you need to choose the right underlayment for your roof.

The underlayment layer is installed underneath the roofing system to provide improved protection against water infiltration and weather elements. If you’re looking to choose a perfect roofing underlayment for your metal roof, read on.


What is a Metal Roof Underlayment?

Underlayment serves as a water-resistant barrier that protects your home from moisture intrusion and weather impacts. It is installed right under the top roofing layer. Some of the most common options are self-adhering membrane, synthetic sheet, and felt.

In absence of the right underlayment, your roof and home can become highly vulnerable to the elements like moisture and wind. A properly installed underlayment can also stop resin chemicals from leaching into the inner layers of your roofing system. Therefore, choosing and installing a suitable underlayment for your roof is the most effective way to protect your home and roof as well as extend its useful life.

How to Choose Underlayment for My New Metal Roof?

While most people know that underlayment is a crucial part of a shingle roof, they are not aware of its importance in a metal roof. A common misconception among property owners is that underlayment is not essential in metal roofs. No doubt, metal roofs are exceptionally durable and structurally sound on their own but having a sturdy underlayment under your metal roof can be immensely beneficial to your home as well as the roof.

Besides protecting your home and roofing system from moisture infiltration, a high-quality underlayment can help prevent condensation issues in your attic. Without an underlayment, moisture can infiltrate your attic and speed up the deterioration of your metal roofing system from the inside out. However, if you have a metal roof, remember to choose an underlayment material with a lifespan nearly equal to the lifespan of your metal roof. This is important to make sure that the entire system stays properly intact for years to come.

Popular Underlayment Options: 

1. Felt Underlayment

Commonly known as felt paper, asphalt-soaked paper, or tar paper, this type of underlayment is commonly used under steep-sloped metal roofing systems. One major reason behind its tremendous popularity is its affordability. It is one of the cheapest underlayment materials on the market.

However, when it comes to roofing underlayment, you get what you pay for. Though felt is highly water-resistant, it cannot withstand high temperatures as effectively as other options. Secondly, this underlayment is not as long-lasting as many other options. So, asphalt felt underlayment is likely to deteriorate much faster than your metal roofing. Lastly, this underlayment is not the right option for low-slope metal roofs.

2. Self-Adhering Membrane

This type of underlayment is applied directly to the roof decking. Essentially a peel-and-stick membrane, self-adhering underlayment is a much better option than the traditional felt membrane, especially if you live in a high-temperature region. The self-adhering membrane is usually made of butyl-based adhesive or rubberized asphalt. A properly installed self-adhering membrane serves as an effective air barrier and can help prevent ice dam formation in places like valleys, dormers, and eaves.

On the flip side, the self-adhering membrane doesn’t perform well in low-temperature environments. Another important factor to keep in mind is to ensure their proper installation. A flawless installation is necessary so that it doesn’t peel back within a few years, leaving your roof prone to water damage.

3. Synthetic underlayment

This type of underlayment is made by spinning or weaving polypropylene (or polyethylene) with some polymer. It forms a sturdy protective barrier that is installed between the decking and roof material. Synthetic underlayment offers several benefits to property owners. It is exceptionally durable because of the use of thermoplastic polymers. It is highly resistant to tearing and moving. Synthetic underlayment also offers excellent protection against moisture damage. 

Looking For Top Quality Underlayment for Your Metal Roof? Contact Republic

At Republic Roofing, we are known for installing top-quality roofing systems and underlayment with unrivaled workmanship and customer service. For more information, contact Republic Roofing at 901-437-5278. We service areas in Lakeland, Germantown, Bartlett, Memphis, and Collierville, TN.