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Johns Manville Retro-Fit Perlite-Based Roof Cover Board, 0.5 in. x 4 ft. x 4 ft.
Regular price $10.13Orders start at $399 — combine any items to reach the minimum. Learn more
Johns Manville Retro-Fit Perlite-Based Roof Cover Board, 0.5 in. x 4 ft. x 4 ft.
This is a Johns Manville Retro-Fit perlite-based roof cover board in a 0.5 in. thickness and 4 ft. x 4 ft. panel size, sold per piece. It provides a suitable surface for adhering or mechanically fastening low-slope roofing membranes over an existing roof assembly. One board covers 16 sq. ft., so plan 9 boards per roofing square before waste.
Key Features:
- Perlite-based core: Manufactured from perlite-based material for use as a cover board in commercial low-slope roofing assemblies.
- UL Classified: This item is UL Classified.
- FM Approved: This item is FM Approved.
- Miami-Dade approved: Approved by Miami-Dade County for use in roofing applications.
- ASTM C728 Type 2: Meets ASTM C728, Type 2, the standard specification for perlite-based roof insulation.
- Lightweight panel: Weighs approximately 7.86 lb per 4 ft. x 4 ft. board for easier handling on the roof.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | Johns Manville |
| Manufacturer model | 90000690 |
| Sell unit | 1 board, 0.5 in. x 4 ft. x 4 ft. |
| Product line | Retro-Fit |
| Material | Perlite-based cover board |
| Dimensions | 4 ft. x 4 ft., 0.5 in. thick |
| Thickness | 0.5 in. |
| Coverage per unit | 16 sq. ft. per board |
| Applicable standards | UL Classified; FM Approved; Miami-Dade County Approved; ASTM C728, Type 2 |
| Weight | 7.86 lb per board |
| Intended use | Roof cover board for low-slope commercial roofing assemblies |
| QXO category | Roofing Insulation |
Coverage & How Much You Need:
Each 0.5 in. x 4 ft. x 4 ft. board covers 16 sq. ft. of roof area. Allow 9 boards per 100 sq. ft. (one roofing square) plus cutting waste around penetrations and edges.
Fit and Compatibility:
Designed for use in Johns Manville commercial roofing systems as a cover board over an existing roof before installing JM membranes, adhesives and fasteners/plates. Membranes, fasteners, plates and adhesives are sold separately; verify fastening pattern with the specified JM system assembly.
Frequently Asked Questions (FAQ):
Q: What is included in this listing?
A: One 0.5 in. x 4 ft. x 4 ft. Johns Manville Retro-Fit perlite-based cover board, sold per piece.
Q: How many boards do I need for a roofing square?
A: Each board covers 16 sq. ft., so nine boards cover a 100 sq. ft. square before cutting waste.
Q: Is this board rated for code and insurance requirements?
A: Yes, this item is UL Classified, FM Approved, Miami-Dade County Approved and conforms to ASTM C728, Type 2.
Q: Can it go over an existing roof?
A: Yes, it is a retro-fit cover board intended to be installed over an existing roof assembly to provide a substrate for a new roofing system; follow the system manufacturer's installation instructions and local code.
Q: How heavy is each board?
A: Each board weighs approximately 7.86 lb, making it easy to carry and position on the roof.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
A 0.5 in. perlite cover board is a cost-effective way to re-cover an existing low-slope roof, providing a smooth, dimensionally stable substrate for a new membrane. Order 9 boards per square plus 5-10% for waste around curbs, drains and edges. Confirm the fastener and plate pattern specified for your JM membrane system, since attachment requirements vary by wind zone.
Follow fall-protection requirements and the membrane system manufacturer's installation instructions when working on commercial roofs.
Order the Johns Manville Retro-Fit 0.5 in. x 4 ft. x 4 ft. perlite cover board for your next roof recover project.
Product Documents:
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