Choosing the best roof felt paper is essential for protecting a structure from moisture, extending shingle life, and improving overall roof performance. This guide explains key types, factors to consider, installation tips, and top options in the current market. It focuses on durability, tear resistance, UV stability, and compatibility with common roofing systems used in American homes.
What Roof Felt Paper Is
Roof felt paper, also called underlayment, is a protective layer installed between the roof deck and shingles. It acts as a moisture barrier, helps shed water, and provides a secondary defense if shingles are damaged. Modern roofing relies on underlayment for wind-driven rain protection and to reduce the risk of leaks during heavy weather. Felt paper comes in organic and fiberglass blends, as well as self-adhering varieties that adhere directly to the roof deck.
Types Of Roof Felt Paper
Understanding the main categories helps homeowners pick the best option for climate, roofing material, and budget.
- Organic Felt: Made from cellulose fibers bound with asphalt. It is robust, affordable, and widely used in older homes. It tolerates minor punctures well but can deteriorate faster in wet conditions over time.
- Fiberglass Felt: Lighter and more tear-resistant than organic options. It resists moisture better, dries quickly, and is common under asphalt shingles in modern construction.
- Self-Adhering Underlayment: Comes with a peel-and-stick backing. It provides excellent water resistance, adheres without fasteners, and is favored in high-wind areas or roofs with many penetrations.
- Water-Resistive Barrier With Asphalt: A newer category that combines asphalt’s waterproofing with a protective granule or paper surface for added durability and easier installation in some climates.
Benefits Of Using The Best Roof Felt Paper
The top-rated roof felt paper delivers reliable moisture protection, reduces the chance of leaks, and enhances the performance of shingles under harsh conditions. Key benefits include:
- Moisture Protection: Acts as a secondary barrier against rain and snow seeping through subtle roof deck gaps.
- Wind Resistance: Provides a continuous layer that helps resist wind-driven infiltration when shingles are damaged or absent during installation.
- Improved Shingle Longevity: Reduces the chance of fastener back-out and blistering by stabilizing the roof assembly.
- Ease Of Installation: Self-adhering and reinforced variants can speed up application and reduce labor time in challenging roof lines.
How To Choose The Best Roof Felt Paper
Selecting the right underlayment involves climate, roof pitch, roof material, and installation method. Consider these criteria:
- Climate And Weather: In areas with heavy rainfall, hail, or rapid temperature shifts, opt for self-adhering or fiberglass underlayment with superior moisture resistance.
- Roofing Material Compatibility: Asphalt shingles commonly pair with fiberglass or self-adhering underlayments, while tile or metal roofs may require specific vapor-permeable or self-adhesive products.
- Wind Conditions: High-wind regions benefit from self-adhering varieties that seal edges more firmly and resist peeling.
- Deck Type And Slope: Steep pitches and rough decks may need stronger, tear-resistant felt; flatter roofs can use standard products without compromising protection.
- UV Exposure: Some underlayments tolerate long outdoor exposure during construction; if the roofing timeline is extended, choose a UV-stable option.
- Installation Method: Self-adhering options reduce fastener use and gaps, while traditional felt requires careful nailing and alignment.
Top Brands And Products For The Best Roof Felt Paper
Market options vary by region, but several brands consistently receive strong reviews for durability and performance. The following are commonly recommended in American homes:
- GAF Pro-12 Self-Adhering Roof Underlayment: Known for reliable self-sealing edges, strong moisture protection, and easy installation on complex roof lines.
- CertainTeed Roof Flex Underlayment: Fiberglass-based, excellent tear resistance, and good wind-driven rain performance.
- IKO ArmorGuard Self-Adhering Underlayment: Robust adhesion, strong puncture resistance, suitable for steep pitches.
- Grace Applying Roof Underlayment: Organic or fiberglass options with budget-friendly performance and broad compatibility.
- DEWALT And Other Premium Laminated Underlayments: Specialty options offering enhanced UV resistance and quick-install features for professional crews.
When evaluating products, check for certifications such as ASTM standards, wind uplift ratings, and compatibility notes with your shingle manufacturer recommendations.
Installation Tips For The Best Roof Felt Paper
Proper installation is as important as product choice. Following best practices helps maximize protection and service life.
- Surface Prep: Ensure the roof deck is clean, dry, and free of protrusions. Repair any damaged decking before applying underlayment.
- Seams And Edges: Overlap seams according to manufacturer instructions, typically 2-4 inches, and extend under shingles at edges to create a continuous barrier.
- Fastening: For traditional felt, use galvanized nails or staples with the correct spacing. Avoid over-tensioning which can cause wrinkles.
- Ventilation: Maintain proper ventilation around attic spaces to prevent condensation that can degrade underlayment.
- Self-Adhering Application: Remove the release film slowly while pressing the material onto the deck to avoid air pockets. Ensure full contact along edges and at penetrations.
- Weather Window: Schedule installation in dry weather; extreme heat can affect some products’ adhesive properties.
Maintenance And Replacement
Underlayment typically lasts 15-30 years depending on climate, roof type, and exposure. Inspect after major storms and during routine roof checks. Signs that underlayment needs attention include increased water staining on the ceiling, damp attic insulation, or visible gaps at seams in exposed areas. In some cases, a roof with damaged underlayment may require partial removal and replacement of the affected area, especially near penetrations or valley lines.
Common Mistakes To Avoid
Avoid these pitfalls to ensure the best performance from roof felt paper:
- Inaccurate Overlap: Cutting corners on seam overlaps undermines moisture protection.
- Inadequate Fastener Use: Too few fasteners can cause buckling or wind uplift.
- Skipping Roof Deck Prep: Failing to fix damaged decking leads to premature underlayment failure.
- Wrong Product For Climate: Using a product not designed for local weather conditions reduces effectiveness.
- Ignoring Manufacturer Guidelines: Deviating from installation instructions voids warranties and reduces protection.
Frequently Asked Questions
Q: Should I use self-adhering underlayment for my asphalt shingles?
A: Self-adhering underlayment provides superior moisture resistance and wind uplift protection, especially in exposed or windy areas.
Q: Can roof underlayment be installed over old underlayment?
A: It is generally not recommended to layer underlayment over existing layers; remove the old layer to ensure proper adhesion and seal.
Q: How do I know which underlayment is compatible with my shingles?
A: Check the shingle manufacturer’s installation guide for compatible underlayments and wind uplift ratings.