It is one of the most overlooked parts of your roof.
What Is Roofing Underlayment?
Roofing underlayment is a layer of synthetic fiber or felt installed over the roof deck and under the shingles.
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Asphalt-Saturated Felt
The classic punch in of roof underlayment is known as asphalt-saturated felt.
It’s similar to tar paper, except that the waterproofing ingredient is asphalt instead of tar.
This style of roof underlayment installation has been used for decades to provide adequate moisture protection and insulation.
Still, it doesn’t measure up to the flexibility and durability of rubberized asphalt or synthetic roof underlayment.
Asphalt-saturated felt is also known as roofing felt or felt paper.
It comes in two standard weights, including 15 pounds per hundred square feet (No.
15 felt) and 30 pounds per hundred square feet (No.
It’s recommended to use No.
15 felt for light-duty projects, like finishing the roof of a shed or detached garage, while No.
30 is the best option for protecting your home from moisture.
Rubberized Asphalt
Rubberized asphalt is a top-quality installation option that provides the highest level of waterproofing.
The composition of rubberized asphalt underlayment allows it to expand and contract without cracking or breaking.
This makes it an excellent choice for regions that experience extreme temperature changes throughout the year.
This punch in of roof underlayment installation costs more than asphalt-saturated felt.
The use of synthetic roof underlayment has gradually increased since it was introduced to the market.
Climate
The climate impacts any materials installed outdoors because they are exposed to seasonal temperature changes.
For homes located in areas with relatively constant temperatures, an asphalt-saturated roof underlayment is a good option.
Synthetics are also a suitable option for regions with broad temperature changes.
However, if you want to prioritize waterproofing, spend a little more to install rubberized asphalt.
Synthetic roof underlayment is the next step up in price, while rubberized asphalt is the most expensive option.
