Tarco Asphalt Saturated Organic Felts
Q. Where are Asphalt Saturated Felt Underlayments used?
A. They are used in a residential roof system between the roof deck and the primary roof covering. Felts are also used between exterior sub-walls and the primary exterior wall covering for moisture control.
Q. Why is the product required under asphalt shingles?
A. When used under asphalt shingles it serves as a secondary water resistant membrane against wind-driven rain. Asphalt shingles by themselves are individual roofing components that are subject to uplift by strong wind. Rain that is blown under the shingle is subject to leaking through a seam in the roof decking without a Felt Membrane to deflect it.
Q. What other benefits do they provide?
A. Asphalt Saturated Organic Felts provide protection from rain in the case individual shingles are damaged or dislodged. Underlayments also minimize "picture framing" of shingles, which is the visible outline of deck panels typically caused by irregularities in roof decking. Underlayments protect asphalt shingles from resins in plywood substrates that can cause damage and a shorter life.
Q. Is there any effect on the Class of fire rating my roof will receive by using an asphalt organic felt underlayment?
A. Yes. Using the appropriate Underlayments along with the proper decking materials and shingles will help in meeting Class A and/or Class C fire ratings. A shingle by itself is not fire-rated, although it is part of a roof assembly. In many municipalities, a Class A and/or a Class C fire rating is required by code or ordinance for all roofing assemblies.
Q. When should asphalt saturated organic felt be covered?
A. Immediately! Asphalt saturated organic felt underlayments by themselves are not a waterproof roofing system. Underlayments should be covered by the primary roof covering immediately to protect the integrity of the material as a secondary water-resistant membrane within the roof system.
Q. How should felt underlayments be stored and under what conditions be applied?
A. They should be stored on end and in the dry. Underlayments should be applied to a smooth, dry roof deck, free of debris. Care should be taken not to damage the product with foot traffic once applied. Damaged product should be replaced before covering.
Q. What are the roll dimensions?
A. Typically the product comes in 2 Square (200 s.f. of roof coverage) or 4 square (400 s.f. of coverage) rolls and a variety of weights. See specifications for more information.
Q. Are MSDS sheets available?
A. Yes. Click here to view. Click here to download Adobe Acrobat.
