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Your roof is your home’s first defense against the elements, but what about the materials underneath your shingles? If you’ve ever wondered, Is roofing felt waterproof?, you’re not alone. Many homeowners and contractors rely on roofing as a critical layer of protection for residential and commercial roofs. At Riverside Roofing, we know the importance of using the proper underlayment to ensure your roof remains durable, leak-free, and capable of withstanding harsh weather conditions. In this guide, we’ll break down what roofing felt is, how waterproof it is, and why it’s a crucial component of any roofing system. Understanding Roofing Felt: What Is It? Roofing felt, sometimes called felt underlayment or felt paper, is a layer of protective material installed between your roof deck and shingles. It’s typically made from a base of either organic fibers or fiberglass, saturated with asphalt or tar to enhance durability and waterproofing. At Riverside Roofing, we always recommend using high-quality felt underlayment to add an extra layer of protection between your shingles and the roof deck. Is Roofing Felt Waterproof? The Truth About Protection The short answer is: Yes, but with limitations. Roofing felt is water-resistant, meaning it can shed water to some extent but isn’t wholly impervious to prolonged moisture exposure. Felt protects the roof deck by creating a temporary waterproof barrier, especially during installation before shingles are placed. At Riverside Roofing, we advise using high-grade roofing felt combined with proper installation techniques to enhance waterproofing performance. Why Roofing Felt Matters in Roof Protection Without felt underlayment, your roof deck is directly exposed to moisture, leading to premature deterioration. Here’s why roofing felt is essential: Prevents Moisture Damage: Stops rain and condensation from seeping into your deck before shingles are installed. Adds an Extra Layer of Defense: Acts as a felt waterproof barrier against leaks. Improves Shingle Performance: Provides a smooth, even surface for shingle installation. Riverside Roofing always emphasizes the importance of a well-installed roofing felt layer to maximize your roof’s lifespan. Types of Roofing Felt: Choosing the Right One There are two main types of felt underlayment to consider: Fifteen-Pound Felt vs. Thirty-Pound Felt Fifteen-pound felt: Lighter, cost-effective, and suitable for residential roofs. Thirty-pound felt: Thicker, more durable, and better suited for steep-slope or commercial applications. At Riverside Roofing, we help homeowners choose the right roofing materials based on their specific needs and climate conditions. How Roofing Felt Protects Your Home Properly installed roofing felt provides essential protection by: Preventing leaks: Acts as a secondary shield against water penetration. Reducing tar and shingle adhesion: Stops shingles from sticking to the roof deck. Enhancing fire resistance: Some felt underlayment products add an extra layer of fire protection. Riverside Roofing ensures expert installation to maximize these benefits. Is Roofing Felt Necessary for Flat Roofs? For flat roof systems, roofing felt is less common, but some contractors still use it as part of a multi-layer waterproofing system. Instead, materials like rubber membranes or modified bitumen provide better protection. If you have a flat roof, consult Riverside Roofing for the best waterproofing solution. Common Mistakes to Avoid with Roofing Felt Installing roofing felt incorrectly can lead to leaks and premature roof failure. Here are some mistakes to avoid: Overlapping too little or too much – This can create gaps or bulges. Using low-quality felt – Cheap materials deteriorate faster. Improper fastening – Staples and nails should be placed correctly to avoid tearing. At Riverside Roofing, we use only high-quality roofing materials and follow best practices to ensure a flawless roof installation. How Long Does Roofing Felt Last? The lifespan of roofing felt depends on several factors, including weather conditions, installation quality, and maintenance. Typically, felt underlayment lasts: 5-10 years if exposed to harsh weather. 20-30 years when properly installed and covered by shingles. For roof replacement or repair, trust Riverside Roofing to assess and replace worn-out felt underlayment before it leads to bigger issues. When to Replace Roofing Felt You should consider roof replacement or felt underlayment replacement if: You notice visible felt waterproof deterioration. Your roof deck is exposed due to missing shingles. You experience frequent leaks despite having a roofing felt layer. If your felt paper is worn out, Riverside Roofing can help with a timely roof replacement to protect your home from further damage. Protect Your Roof with Quality Roofing Felt So, is roofing felt waterproof? While it offers a good level of waterproofing, it works best when installed correctly and combined with high-quality shingles. Whether you're installing a new roof, repairing a residential or commercial structure, or considering a roof replacement, Riverside Roofing is here to help. Don’t leave your roof’s protection to chance—contact Riverside Roofing today for expert guidance and premium roofing services.

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