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TRI-BUILT 3.0 in. x 4 ft. x 8 ft. Polyiso ISO Rigid Roof Insulation Board
Regular price $53.73Orders start at $399 — combine any items to reach the minimum. Learn more
TRI-BUILT 3.0 in. x 4 ft. x 8 ft. Polyiso ISO Rigid Roof Insulation Board
This TRI-BUILT ISO rigid roof insulation board is a 3.0 in. thick polyisocyanurate panel in a 4 ft. x 8 ft. sheet, sold as one piece. Its added thickness helps reach target R-value in fewer layers and it pairs with cover boards, adhesives and membrane systems in the roof build-up.
Key Features:
- Rigid polyiso core: Polyisocyanurate rigid foam board for low-slope roof insulation.
- Full 4x8 sheet: Each board measures 4 ft. x 8 ft., providing 32 sq ft of area.
- Thick 3.0 in. panel: 3.0 in. thickness builds insulation value quickly in fewer lifts.
- Manageable weight: Weighs approximately 16.5 lb per board despite the added thickness.
- Flat board format: Rigid sheet lays flat for clean joints and easy multi-layer staggering.
- Single-piece ordering: Sold per piece so quantities match the insulation layout.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | TRI-BUILT |
| Manufacturer model | TB-316960 |
| Sell unit | 1 board, 4 ft. x 8 ft. x 3.0 in. |
| Product line | TRI-BUILT ISO Rigid Roof Insulation |
| Material | Polyisocyanurate (polyiso) rigid foam |
| Nominal size | 4 ft. x 8 ft. |
| Thickness | 3.0 in. |
| Coverage per unit | 32 sq ft per board |
| Weight | 16.48 lb per board |
| Intended use | Rigid roof insulation for low-slope roofing assemblies |
Coverage & How Much You Need:
One 4 ft. x 8 ft. board covers 32 sq ft. Divide total roof area by 32 for a board count, then add for cuts and perimeter waste.
Fit and Compatibility:
Installed as rigid insulation in low-slope roof assemblies with cover boards, insulation adhesives and membranes. Attachment pattern must follow the roofing system manufacturer's requirements and local code.
Frequently Asked Questions (FAQ):
Q: What is included in the sell unit?
A: One 3.0 in. thick, 4 ft. x 8 ft. polyiso insulation board.
Q: How many boards for my roof?
A: Each board covers 32 sq ft; divide your area by 32 and add for cut waste.
Q: How is this thickness installed?
A: Boards are mechanically fastened or adhered per the roofing system manufacturer's instructions and local code.
Q: Can I combine it with thinner boards?
A: Yes, thick base layers are often combined with thinner lifts to reach total design thickness.
Q: How much does one board weigh?
A: Approximately 16.48 lb.
Q: Is on-site cutting possible?
A: Yes, score and cut rigid polyiso with a utility knife or insulation saw.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
Choosing a 3.0 in. polyiso board reduces the number of lifts needed to reach design R-value, saving labor on larger low-slope roofs. Stage boards flat, keep them dry, and stagger joints between layers. Verify fastener length and wind-uplift attachment with the membrane system manufacturer before installation.
Wear gloves, eye protection and a dust mask when cutting rigid foam, and follow the roofing system manufacturer's installation instructions and local code.
Order TRI-BUILT 3.0 in. ISO rigid roof insulation boards to reach your design thickness in fewer lifts.
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