Roof felt tar paper is one of the most commonly used roofing underlayments. This durable material acts as a protective layer between the roof deck and the external roofing materials, providing a barrier against moisture and improving the roofing system’s overall performance.
What is Roof Felt?
Roof felt is made from a base material, such as paper or fiberglass, saturated with asphalt to enhance its water resistance and durability. It is typically available in rolls of varying thicknesses, denoted by weight grades such as 15-pound and 30-pound felt, which refer to the material’s weight per 100 square feet.
Features of Roof Felt
- Material Composition:
- Made from organic paper or fiberglass, it is impregnated with asphalt for weatherproofing.
- Thickness Options:
- Common grades include:
- 15-pound felt: Lightweight and suitable for basic protection.
- 30-pound felt: Thicker and more durable, ideal for enhanced protection.
- Common grades include:
- Water Resistance:
- Designed to repel water and protect the roof deck from moisture infiltration.
- Breathability:
- Allows moisture to escape, reducing the roof deck’s mold and rot risk.
- Temporary Protection:
- Provides short-term protection for the roof deck during installation before the final roofing material is applied.
Benefits of Roof Felt
- Waterproofing:
- Acts as a secondary barrier against water penetration, especially during storms or heavy rainfall.
- Affordable:
- Cost-effective compared to modern synthetic underlayments, making it a popular choice for budget-conscious projects.
- Ease of Installation:
- Lightweight and easy to cut, roof felt can be installed quickly and efficiently.
- Enhanced Longevity:
- Protects the roof deck from damage, extending the lifespan of the overall roofing system.
- Fire Resistance:
- Provides an additional layer of fire resistance in some applications.
Limitations of Roof Felt
- Susceptible to Tearing:
- Can tear or wrinkle during installation, especially in high winds or if mishandled.
- Limited Lifespan:
- Deteriorates faster than synthetic alternatives when exposed to prolonged UV light or extreme weather.
- Less Durable in Extreme Conditions:
- Not as resistant to heat, cold, or heavy foot traffic as synthetic underlayments.
Installation Process
- Roof Deck Preparation:
- Ensure the roof deck is clean, dry, and free of debris.
- Rolling Out the Felt:
- Start at the roof’s eaves and roll the felt horizontally, overlapping each row by at least 2 inches.
- Fastening the Felt:
- Secure the felt with staples or roofing nails, ensuring consistent spacing and secure attachment.
- Overlapping Edges:
- Overlap edges and seams to create a continuous barrier against water infiltration.
- Edge and Valley Treatment:
- Pay extra attention to sealing around valleys, edges, and penetrations for maximum protection.
Maintenance Tips for Roof Felt
- Inspect Regularly:
- Check for wrinkles, tears, or signs of wear, especially if the felt is exposed for an extended period.
- Repair Damaged Sections:
- Patch or replace torn areas promptly to maintain the roofing system’s integrity.
- Replace During Re-Roofing:
- Roof felt should be replaced whenever the outer roofing material is removed to ensure continued protection.
- Ensure Proper Ventilation:
- Adequate attic ventilation helps prevent moisture buildup that could compromise the felt’s effectiveness.
Applications of Roof Felt
- Residential Roofs:
- Commonly used under asphalt shingles for added protection and moisture resistance.
- Commercial Properties:
- Suitable for smaller commercial projects where budget-friendly solutions are preferred.
- Temporary Roof Protection:
- Often used to shield the roof deck during construction or repairs before the final roofing material is installed.
Why Choose Roof Felt?
Roof felt remains a trusted choice for many roofing projects due to its affordability, ease of use, and reliable performance. While synthetic underlayments offer advanced features, roof felt provides a time-tested solution that delivers effective protection against water and extends the roofing system’s life.
Conclusion
Roof felt is a dependable and cost-effective roofing underlayment that has been a staple in the industry for decades. Its ability to protect the roof deck from moisture and enhance the overall durability of the roof makes it an essential component of many roofing systems. Whether for residential or light commercial applications, roof felt is a practical choice for building and maintaining a durable roof.