Do Roofers Use Felt Anymore?
The underlayment is a critical part of a roof’s structure. It prevents water and wind from getting into your home, even when shingles are cracked or damaged.
The most popular material for many years was felt. But is felt on its way out? Does synthetic underlayment do a better job? Our guide explains everything you need to know about these roofing materials.
What is Felt Underlayment?
If your San Antonio roofer is replacing your underlayment, you’ll notice that this isn’t the same fabric you use when teaching your kids to sew toys. As a roofing material, it’s much tougher and more waterproof. It resists drafts and is difficult to tear, which makes it an excellent material when protected by shingles.
Introducing Synthetic Underlayment
In recent years, synthetic underlayment has been growing in popularity. These are plastic-based (typically polypropylene or polyethylene), and many roofers consider them superior to traditional fabrics.
We’ll cover the head-to-head later, but it’s important to note that plastics are far more waterproof than felt fabric. Preventing water damage is perhaps the primary purpose of underlayment, as it can cause harmful rot.
Is Felt Underlayment Still Popular?
Yes! Felt is still the most popular roofing underlayment material in the U.S. Its low cost and durability make it an attractive choice for roofers – it’s also very easy to maintain and replace.
If you ask a San Antonio roofer if they cover felt underlayment replacements, the answer will likely be yes. However, they might also recommend switching to synthetic roofing – let’s find out why.
Felt vs. Synthetic Underlayment: Which is Best for Roofing?
Felt’s key advantage is that it’s extremely cheap to produce. Synthetic materials can be cheaper when produced in super-thin layers, but these aren’t considered ideal. You lose many of the advantageous properties of thicker synthetic rolls when cut that thin.
Let’s consider the materials head-to-head.
Advantages of Felt:
- More affordable
- Widely available
- Easy to repair & install
- Offers good protection from wind & rain
Advantages of Synthetic Underlayment:
- Better wind resistance, preventing drafts in your attic
- Comes in larger rolls, making it preferable for large-scale roofing jobs
- Far more waterproof – this is the main reason that your San Antonio roofer will likely recommend a synthetic underlayment
- Less likely to tear, so if a shingle comes loose, it can withstand adverse weather
- It’s lighter, so your roof takes less strain. The roof’s dead load will also be lighter, making it easier for roofers to work
- Less likely to lift during high winds. Lifting can potentially tear an entire roof away
- Captures less heat – synthetic materials tend to be gray while roofing felt is black. This means less heat being drawn into your San Antonio home
You may be able to guess the winner. Synthetic underlayment has significant advantages over roofing felt.
If you need repairs or you’re considering installing a new roof on your San Antonio property, consider synthetic materials for better and longer-lasting protection. The extra cost is relatively small and will pay itself back as your home will be protected for many years.