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Johns Manville Dynaglas FR 36 in. Bright White SBS Modified Bitumen FR Cap Sheet, 1 Square Roll
Regular price $220.00Orders start at $399 — combine any items to reach the minimum. Learn more
Johns Manville Dynaglas FR 36 in. Bright White SBS Modified Bitumen FR Cap Sheet, 1 Square Roll
Johns Manville Dynaglas FR is a bright white glass-reinforced SBS modified bitumen cap sheet listed at one square per roll. The FR designation indicates a fire-rated construction for low-slope multi-ply assemblies, and it installs over compatible JM base and interply sheets.
Key Features:
- FR construction: FR designation denotes a fire-rated cap sheet for approved assemblies.
- Glass reinforcement: CR glass mat reinforcement provides dimensional stability.
- Bright white top: Bright White surfacing delivers a reflective cap layer.
- Full square roll: Each roll covers one square.
- SBS flexibility: SBS modified asphalt resists cracking at low temperatures.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | Johns Manville |
| Sell unit | 1 roll |
| Product line | Johns Manville Dynaglas FR Cap Sheet |
| Membrane type | SBS modified bitumen |
| Available colors | Bright White |
| Coverage per unit | 1 square per roll |
Coverage & How Much You Need:
One roll covers one square (100 sq ft); allow additional material for side and end laps when estimating.
Fit and Compatibility:
Designed as the cap layer in Johns Manville multi-ply low-slope assemblies over compatible JM base and interply membranes. Base sheets, adhesives, mastic and fasteners are sold separately.
Frequently Asked Questions (FAQ):
Q: How much does one roll cover?
A: One square, about 100 sq ft, before laps and waste.
Q: What does FR mean?
A: It designates a fire-resistant construction; final rating depends on the complete approved assembly.
Q: What color is the top surface?
A: Bright White.
Q: Can it be used alone?
A: No, it is a cap sheet and should be installed as the top layer of a multi-ply system.
Q: How many rolls per square?
A: One roll is listed at one square per roll.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
Use Dynaglas FR where the specified assembly calls for a fire-rated glass-reinforced white cap sheet. Verify the full system specification, since fire performance depends on the entire roof build-up, not the cap alone. Plan laps and flashings before ordering to avoid running short on a one-square-per-roll product.
Verify the approved assembly with the membrane manufacturer and local code authority, as fire ratings apply only to complete installed systems.
Order Johns Manville Dynaglas FR bright white cap sheet for fire-rated multi-ply roofing work.
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