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Roofing Felt

Roofing felt, also known as tar paper or felt paper, is a material used in roofing systems as an underlayment to provide an additional layer of protection against moisture and weather elements. Made from a combination of cellulose fibers, asphalt, and other materials, roofing felt is typically produced in large rolls and is installed beneath shingles or other roofing materials.

There are two primary types of roofing felt: organic and fiberglass. Organic felt is made from recycled paper products, while fiberglass felt is composed of a glass fiber mat coated with asphalt. Both types offer waterproofing capabilities, but fiberglass felt is generally more durable and resistant to tearing.

Roofing felt serves multiple purposes, including acting as a moisture barrier, providing insulation, and reducing the likelihood of leaks. It is a crucial component in roofing applications, ensuring the longevity and effectiveness of the roofing system.

Why it Matters?

  • Moisture Protection: Roofing felt provides a crucial barrier against moisture intrusion, protecting the underlying roofing structure and preventing potential damage.

  • Increased Durability: By adding an additional layer of protection, roofing felt can extend the lifespan of the roofing materials, reducing maintenance and replacement costs over time.

  • Fire Resistance: Many types of roofing felt are treated to enhance their fire-resistant properties, adding an extra layer of safety to the roofing system.

  • Weather Resistance: Roofing felt helps to mitigate the effects of extreme weather conditions, including rain, snow, and wind, thereby maintaining the integrity of the roof.

Industry Standards/Regulations

  • ASTM International: Sets standards for roofing felts, including ASTM D226 (standard specification for asphalt-saturated organic felt) and ASTM D4869 (standard specification for fiberglass felt).

  • Underwriters Laboratories (UL): Provides ratings for roofing materials, including fire-resistance ratings for roofing felts, ensuring compliance with safety standards.

  • International Building Code (IBC): Establishes requirements for roofing systems, including the use of underlayment materials like roofing felt to promote safety and performance.

Common Uses/Applications

  • Underlayment for Shingles: Roofing felt is commonly installed beneath asphalt shingles to provide waterproofing and protection against leaks.

  • Flat Roof Applications: In low-slope roofing systems, felt serves as an essential moisture barrier, especially when used with built-up roofing or modified bitumen systems.

  • Protection During Installation: Roofing felt provides temporary protection for the roof deck while the roofing materials are being installed, helping to prevent water damage.

  • Re-Roofing Projects: When replacing a roof, roofing felt is often used as an underlayment to ensure the new roofing system has proper moisture protection.

FAQs

Q: What is the difference between organic and fiberglass roofing felt?
A: Organic felt is made from recycled paper and is coated with asphalt, while fiberglass felt is composed of a fiberglass mat coated with asphalt. Fiberglass felt is generally more durable and resistant to tearing than organic felt.

Q: Is roofing felt waterproof?
A: Roofing felt is water-resistant but not completely waterproof. It is designed to shed water and provide a moisture barrier but should be used in conjunction with roofing materials for optimal protection.

Q: How is roofing felt installed?
A: Roofing felt is typically installed by rolling it out over the roof deck, overlapping seams by several inches, and securing it with roofing nails or staples. It is important to follow manufacturer instructions for proper installation.

Q: Can roofing felt be used on flat roofs?
A: Yes, roofing felt is commonly used on flat roofs as part of a built-up roofing system or in conjunction with modified bitumen to provide moisture protection.

Q: How long does roofing felt last?
A: The lifespan of roofing felt can vary based on the type, installation method, and environmental conditions, but it typically lasts anywhere from 10 to 20 years when properly installed.

Synonyms

  • Tar Paper

  • Felt Paper

  • Asphalt Felt

Related Terms

  • Underlayment: Any material placed beneath roofing materials to provide additional protection against moisture and weather elements.

  • Asphalt Shingles: A common roofing material that is often installed over roofing felt to provide a waterproof barrier.

  • Modified Bitumen: A type of roofing material that can be used with roofing felt for enhanced waterproofing in flat roofing systems.

  • Roof Deck: The structural surface to which roofing materials are applied, which may benefit from the added protection of roofing felt.

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