15# vs 30# Roofing Felt: Which Should You Choose?: Fast-Track Guide to Choosing the Right Roofing Felt for Your Project

When it comes to roofing projects, one fundamental choice is between 15# and 30# roofing felt. Both are types of asphalt-saturated underlayment that serve as protective layers between your roof deck and the shingles. But how do you decide which one is best for your needs? As a designer, I always view these options not just from a technical standpoint, but also from their impact on overall design integrity and the longevity of your home.

15# Roofing Felt: This is the lighter and thinner option. It’s easier to handle and install, making it a popular choice for standard residential projects with a lower budget or where weight is a concern. 15# felt offers basic protection against moisture, but it’s more susceptible to tearing, especially during installation or in high winds. It’s suitable for roofs with a steeper pitch where water is less likely to pool.

30# Roofing Felt: Thicker and heavier, 30# felt adds a layer of durability. It’s less likely to tear and provides enhanced protection, particularly for roofs exposed to harsh weather or with a lower pitch where water runoff is slower. While it is more challenging to work with due to its weight, it often results in greater overall security and peace of mind for important or long-lasting projects.

From a design perspective, the choice can influence maintenance cycles and overall home resilience. If you’re planning a high-end home renovation or want to ensure longevity and better moisture defense, roofing underlayment material selection is a detail that shouldn’t be overlooked. Opting for the heavier felt can also be part of a layered approach that complements insulation and ventilation strategies—key elements in sustainable and comfortable interior design.

Tips 1:

Always match your roofing felt to your climate and roof pitch: use 15# for quick renovations and steeper roofs, and 30# for added durability or lower slopes. As a designer, I also recommend considering longevity and maintenance when making your choice, as these factors can have a direct effect on the interior comfort and value of your home.

FAQ

Q: What is the main difference between 15# and 30# roofing felt?

A: The primary difference lies in their thickness, weight, and durability. 30# felt is thicker, heavier, and more durable, providing better protection than 15# felt.

Q: Is 30# roofing felt always better than 15# felt?

A: Not necessarily. While 30# felt offers more durability, 15# felt might be adequate for steep, low-risk roofs or when budget and ease of installation are priorities.

Q: How do I choose the right roofing felt for my home?

A: Consider climate, roof pitch, how long you want the roof to last, and your budget. For harsh weather or shallow pitches, 30# is typically better suited.

Q: Can I use 15# and 30# felt together?

A: In some cases, combining both can provide layered protection, but it’s uncommon and should only be done if recommended by a roofing professional.

Q: How does roofing felt affect my home’s overall design?

A: The right choice in underlayment can extend the lifespan and reduce the maintenance needs of your roof, directly impacting down-the-road refurbishment costs and even influencing the interior environment.