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TRI-BUILT 1 in. x 4 ft. x 8 ft. ISO II GRF Polyiso Roof Insulation Board
Regular price $28.42Orders start at $399 — combine any items to reach the minimum. Learn more
TRI-BUILT 1 in. x 4 ft. x 8 ft. ISO II GRF Polyiso Roof Insulation Board
This TRI-BUILT ISO II GRF roof insulation board is a 1-inch-thick, 4 ft. x 8 ft. polyisocyanurate panel for low-slope roof assemblies, ideal as a base layer or thin lift. One board covers 32 sq ft and is sold per piece.
Key Features:
- 1 in. thickness: One-inch panel suits base layers or thin insulation lifts.
- 4 ft. x 8 ft. board: Standard 32 sq ft board for efficient coverage.
- GRF facer: Glass-reinforced facer in the ISO II line.
- Polyiso core: Polyisocyanurate foam insulation for low-slope roofing.
- Light handling: Approximately 7.84 lb per board for easy job-site handling.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | TRI-BUILT |
| Manufacturer model | AC2_PL_004 |
| Sell unit | 1 board, 1 in. x 4 ft. x 8 ft. |
| Product line | ISO II GRF Roof Insulation |
| Dimensions | 4 ft. x 8 ft., 1 in. thick |
| Thickness | 1 in. |
| Coverage per unit | 32 sq ft per board |
| Material | Polyisocyanurate foam insulation |
| Weight | 7.84 lb |
Coverage & How Much You Need:
Each 1 in. x 4 ft. x 8 ft. board covers 32 sq ft. Divide the roof area by 32 and allow for cuts and waste; boards are also counted by the square (100 sq ft).
Fit and Compatibility:
Used in low-slope roof assemblies beneath approved membranes, often layered with thicker ISO boards. Attachment plates and adhesives are sold separately; install per the membrane manufacturer's requirements.
Frequently Asked Questions (FAQ):
Q: What size is each board?
A: Each board is 4 ft. x 8 ft. and 1 inch thick, covering 32 sq ft.
Q: How many boards do I need?
A: Divide the roof area by 32 sq ft per board and allow for waste.
Q: What is GRF?
A: GRF refers to the glass-reinforced facer on this ISO II board.
Q: How much does a board weigh?
A: Approximately 7.84 lb per 1-inch board.
Q: Can it be layered with thicker boards?
A: Yes, thinner boards are commonly used as base or intermediate layers in multi-layer assemblies.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
Thin polyiso lifts are commonly used as base layers under thicker boards in staggered-joint, multi-layer assemblies to reduce thermal bridging. Verify attachment method and layer order with the membrane manufacturer and local code. Confirm the project's total R-value needs before selecting thickness.
Store boards flat and dry and secure them against wind on the rooftop.
Order the TRI-BUILT 1 in. ISO II GRF polyiso roof insulation board for your next low-slope roofing job.
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