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Johns Manville SeparatoR CGF 1/2 in. x 4 ft. x 8 ft. Polyiso Roof Board
Regular price $38.99Orders start at $399 — combine any items to reach the minimum. Learn more
Johns Manville SeparatoR CGF 1/2 in. x 4 ft. x 8 ft. Polyiso Roof Board
This is a Johns Manville SeparatoR CGF polyiso roof board, 1/2 in. thick and 4 ft. x 8 ft., for commercial low-slope roofing insulation and cover board use. One sell unit is a single panel. It installs in JM roofing assemblies under the membrane with attachment per the system specification.
Key Features:
- Polyiso core: Polyisocyanurate roof board with CGF facers in a 4 ft. x 8 ft. panel.
- Lightweight panel: Approximately 8.09 lb gross weight per panel.
- Standards listed: ASTM C1289 Type II, Class 2, Grade 3; FM Approved; UL Classified.
- Green building credit: Listed as contributing to LEED requirements.
- Canadian standard: Meets the requirements of CAN/ULC S704, Type 3, Class 3.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | Johns Manville |
| Manufacturer model | 90027859 |
| Sell unit | 1 panel, 1/2 in. x 4 ft. x 8 ft. |
| Product line | SeparatoR CGF |
| Dimensions | 4 ft x 8 ft, 1/2 in. thick |
| Thickness | .5 in. |
| Coverage per unit | 32 sq ft per panel |
| Material | Polyisocyanurate (polyiso) roof board |
| Approvals | ASTM C1289, Type II, Class 2, Grade 3; FM Approved; LEED; Meets the Requirements of CAN/ULC S704, Type 3, Class 3; UL Classified |
| Weight | 8.09 lb gross per panel |
| Intended use | Commercial low-slope roofing insulation/cover board |
Coverage & How Much You Need:
Each 4 ft. x 8 ft. panel covers 32 sq ft. Divide the roof area by 32 to estimate panel count and add a small cutting allowance.
Fit and Compatibility:
Designed for use in Johns Manville commercial roofing assemblies under JM membranes. Fasteners, plates or adhesives are sold separately per the specified JM system.
Frequently Asked Questions (FAQ):
Q: What is included?
A: One 1/2 in. thick, 4 ft. x 8 ft. SeparatoR CGF polyiso roof board panel.
Q: How much does one panel cover?
A: 32 sq ft; divide your roof area by 32 and allow extra for cuts.
Q: Which standards does it meet?
A: ASTM C1289 Type II, Class 2, Grade 3; FM Approved; UL Classified; CAN/ULC S704 Type 3, Class 3; and it is listed for LEED.
Q: How is the board attached?
A: Per the JM system specification, typically with mechanical fasteners and plates or approved adhesive, sold separately.
Q: How heavy is a panel?
A: The listed gross weight is approximately 8.09 lb per panel.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
SeparatoR CGF is JM's polyiso board for insulation and cover board roles; the 1/2 in. thickness is common for cover board over other insulation or as a thermal layer per the assembly R-value design. Verify the specified thickness and fastening pattern in your JM assembly, and keep boards dry and flat until the membrane is applied.
Follow OSHA fall protection rules on commercial roofs and lift boards with proper technique to avoid strain.
Order the Johns Manville SeparatoR CGF 1/2 in. 4 ft. x 8 ft. polyiso roof board today.
Product Documents:
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