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GAF RUBEROID 20 Smooth Membrane - SBS Modified Bitumen Base or Interply Membrane, Black 39.375 in. x 49 ft. 2 in. Roll
Regular price $96.50Orders start at $399 — combine any items to reach the minimum. Learn more
GAF RUBEROID 20 Smooth Membrane - SBS Modified Bitumen Base or Interply Membrane, Black 39.375 in. x 49 ft. 2 in. Roll
GAF RUBEROID 20 Smooth Membrane is a tough, resilient SBS polymer-modified bitumen roofing membrane with a non-woven glass mat core, supplied in a black 39.375 in. x 49 ft. 2 in. roll. Designed for new roofing, re-cover and flashing construction, it serves as an ideal base or interply membrane in modified bitumen systems, including GAF Composite R.
Key Features:
- SBS Modified Asphalt: A strong non-woven glass mat core coated with flexible, SBS polymer-modified asphalt.
- Base or Interply: Ideal base or interply membrane in modified bitumen systems, including GAF Composite R.
- New Roof and Re-Cover: Designed for new roofing and re-cover applications as well as flashing construction.
- 20-Year Guarantees: System guarantees are available for up to 20 years.
- Lightweight Design: Installed roof designs weigh less than three pounds per square foot.
- GAF Specifications: Manufactured to stringent GAF specifications for consistent performance.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | GAF |
| Sell unit | 1 roll, 39.375 in. x 49 ft. 2 in. |
| Product line | GAF RUBEROID |
| Available colors | Black |
| Available sizes | 39.375" x 49' 2" roll (1 item on this page) |
| Material | SBS polymer-modified bitumen over non-woven glass mat core |
| Dimensions | 39.375 in. x 49 ft. 2 in. |
| Length | 49 ft. 2 in. |
| Width | 39.375 in. |
| Weight | Installed roof designs weigh less than 3 lb per sq ft |
| Intended use | Base or interply membrane for new roofing, re-cover and flashing construction |
| Coverage per unit | roll is approx. 135 sq ft before laps and wastage |
| System | Modified bitumen systems including GAF Composite R |
| Warranty | System guarantees available for up to 20 years |
Coverage & How Much You Need:
Each roll measures 39.375 in. x 49 ft. 2 in., roughly 135 sq ft of material; actual coverage is reduced by side and end laps in multi-ply modified bitumen assemblies. Plan roll counts from roof area plus standard lap allowances.
Fit and Compatibility:
Intended for use as a base or interply membrane in modified bitumen systems, including GAF Composite R. Cap sheets, adhesives or torch application materials for finishing plies are ordered separately per the chosen system.
Frequently Asked Questions (FAQ):
Q: What is included in one order?
A: One roll of GAF RUBEROID 20 Smooth Membrane, black, 39.375 in. x 49 ft. 2 in.
Q: Where is it used in the system?
A: It is designed as a base or interply membrane in modified bitumen systems, including GAF Composite R.
Q: What is the core made of?
A: A strong, resilient non-woven glass mat coated with flexible SBS polymer-modified asphalt.
Q: Is it heavy on the roof?
A: No, installed roof designs weigh less than three pounds per square foot.
Q: Can guarantees be obtained?
A: Yes, system guarantees are available for up to 20 years through the manufacturer's system requirements.
Q: Can it be used for flashings?
A: Yes, it is designed for use in the construction of flashings as well as new roofing and re-cover.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
RUBEROID 20 Smooth is the workhorse base ply for commercial modified bitumen: the glass mat core gives dimensional stability while the SBS asphalt stays flexible in service. Use it under a granulated cap sheet or within GAF Composite R assemblies, and order guarantee-eligible components if a 20-year system guarantee is the project goal. Its low installed weight is useful on decks with load limits.
Follow the manufacturer's application instructions and OSHA hot-work or fall-protection requirements when installing modified bitumen membranes.
Order GAF RUBEROID 20 Smooth Membrane for a proven base or interply in your modified bitumen system.
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