GMC Roofing & Building #30 ASTM Shakefelt Steep Slope Roofing Underlayment, Roll

GMC Roofing & Building #30 ASTM 22″ Shakefelt is a 30-pound ASTM-compliant felt underlayment for steep slope roofs, sold by the roll. Install it over the roof deck beneath shingles or other steep slope coverings. Use with appropriate fasteners and laps per the covering manufacturer’s specifications.

Key Features:

• No. 30 felt: A 30-pound class felt underlayment for steep slope roofing.
• ASTM compliance: Manufactured as #30 ASTM felt.
• 22 in. Shakefelt: Offered as 22-inch Shakefelt.
• Roll format: Supplied by the roll for convenient handling.
• Steep slope use: Intended for use as steep slope roofing underlayment.

Specifications Table:

Coverage & How Much You Need:

Exact roll dimensions and coverage are not stated in the available sources. Standard #30 felt rolls are commonly sized for use beneath shingles with side laps; confirm coverage from the roll label before ordering.

Fit and Compatibility:

Designed for use beneath asphalt shingles and other steep slope roof coverings over an approved deck. Cap nails or cap staples and any drip edge are sold separately.

Frequently Asked Questions (FAQ):

Q: What is included with my order?
A: One roll of GMC Roofing & Building #30 ASTM 22″ Shakefelt underlayment.

Q: How do I size my order?
A: Estimate roof area, allow for side and end laps, and order rolls based on the coverage printed on the roll.

Q: What fasteners should I use?
A: Fasten with roofing nails, cap nails or cap staples per the shingle manufacturer’s underlayment requirements.

Q: Does this meet ASTM standards?
A: It is designated as #30 ASTM felt, per the product listing.

Expert Verdict Reviewed by the SuperArbor Pro Desk

No. 30 ASTM felt is the traditional choice for steep slope shingle underlayment, offering heavier weight and better tear resistance than No. 15. Keep laps consistent and follow the covering manufacturer’s nailing pattern. In high-wind zones, consider specifying the fastening method required by local code.

Roofing underlayment surfaces are slippery; use fall protection and install from ladders or roof brackets safely secured to the structure.

Order GMC Roofing & Building #30 ASTM Shakefelt underlayment rolls for your next shingle roof.