Introduction to Roofing Underlayment

In the realm of roofing repairs and replacements, the choice of underlayment plays a pivotal role in ensuring the longevity and protection of your roof. Two primary contenders dominate the market: traditional felt and modern synthetic underlayment. This article delves into the specifics of each, helping homeowners make an informed decision.

The Basics of Felt Underlayment

Felt underlayment, often referred to as tar paper, is a time-tested option. Made from a blend of natural and synthetic fibers coated in asphalt, it offers a basic level of protection against moisture. Felt comes in two thicknesses: 15-pound and 30-pound, with the latter providing superior durability.

Pros of Felt Underlayment

  • Cost-Effective: Felt is generally more affordable than synthetic options.
  • Ease of Installation: Its heavier weight aids in laying flat against the roof deck.
  • UV Protection: When exposed, it provides short-term UV protection.

Cons of Felt Underlayment

  • Susceptibility to Tear: Felt can tear easily, especially in windy conditions.
  • Water Absorption: It tends to absorb water, which can lead to wrinkling and reduced effectiveness.
  • Weight: Heavier felt options can be more challenging to handle and install.

The Advantages of Synthetic Underlayment

Synthetic underlayment, a newer innovation, is made from woven or spun polyethylene or polypropylene. It’s engineered to offer enhanced protection against a range of elements.

Pros of Synthetic Underlayment

  • Durability: Resistant to tearing, even in high winds or during installation.
  • Water Resistance: Excellent at repelling water and protecting the roof deck.
  • Lightweight: Easier to handle and install, reducing labor time.
  • Long-Term Protection: Offers better long-term UV and moisture protection.

Cons of Synthetic Underlayment

  • Cost: Generally more expensive than felt.
  • Slippery Surface: Can be more slippery than felt when wet, posing a safety risk during installation.

Comparative Analysis: Felt vs. Synthetic

When comparing felt and synthetic underlayment, several factors come into play:

  • Longevity: Synthetic underlayment tends to last lo