Roofing 101: What is Underlayment?
When it comes to roofing, the first things that often come to mind are shingles or metal panels. However, an often overlooked but crucial component plays a pivotal role in protecting your home from the elements: underlayment. As an exterior home improvement contractor specializing in storm and insurance restoration, we’ve seen how underlayment can make or break a roofing system. Roofing underlayment is a layer of material between the roof deck (the structural base) and the visible roofing materials like shingles.
Types of Underlayment
There are primarily three types of underlayment used in roofing:
Felt Underlayment: Often referred to as tar paper, felt underlayment is made from fiberglass or polyester soaked in waterproofing agents. It comes in two thicknesses: 15-pound and 30-pound. The 30-pound version offers superior protection and durability.
Synthetic Underlayment: This type is increasingly popular due to its strength, lightweight nature, and resistance to mold and water. Synthetic underlayment often includes woven or spun-bound polyethylene or polypropylene and can be more resistant to UV degradation. Products such as GAF FeltBuster, GAF Deck-Armor and GAF Tiger Paw are types of synthetic underlayment.
Rubberized Asphalt Underlayment: The most premium option, this self-sealing underlayment provides the highest level of waterproofing. This product is commonly called ice and water shield or leak barrier. It is typically used on the areas of the roof that are prone to water damage, like eaves, valleys, and penetrations, but it can be used on the entire roof deck for the maximum amount of protection. GAF offers WeatherWatch and StormGuard leak barriers.
The Benefits of Underlayment
The primary role of underlayment is to act as a secondary barrier against water infiltration. Even the best shingles can allow water seepage, especially during wind-driven rain or ice damming. The underlayment catches this water and directs it away from the roof structure. This extra level of protection can result in an improved roof lifespan by protecting the roof deck from moisture fluctuations.
Underlayment is crucial for a durable, long-lasting roof. A roof is more than just its outer layer; it's a complex system where each element plays a vital role, especially underlayment. Trust a GAF-certified roofing contractor like Lion Hopper to install your roof correctly. Schedule a roof inspection today!
