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TRI-BUILT 2.6 in. x 4 ft. x 8 ft. Polyiso ISO Rigid Roof Insulation Board
Regular price $58.97Orders start at $399 — combine any items to reach the minimum. Learn more
TRI-BUILT 2.6 in. x 4 ft. x 8 ft. Polyiso ISO Rigid Roof Insulation Board
This TRI-BUILT ISO rigid roof insulation board is a 2.6 in. thick polyisocyanurate panel in a 4 ft. x 8 ft. sheet, sold as a single piece. It provides a continuous rigid foam layer for low-slope roofing assemblies and pairs with roof cover boards, adhesives and membrane systems in the same roof build-up.
Key Features:
- Rigid polyiso core: Made of polyisocyanurate rigid foam insulation for low-slope roof assemblies.
- Full 4x8 sheet: Each board measures 4 ft. x 8 ft., providing 32 sq ft of panel area.
- Thick 2.6 in. panel: At 2.6 in. thick, this board adds substantial insulation value in a single layer.
- Lightweight handling: Weighs approximately 14.75 lb per board for easier job-site handling and cutting.
- Flat board stock: Rigid board format lays flat for tapered or flat roof insulation layouts.
- Single-piece sell unit: Sold by the piece so you can order exactly the number of boards your layout requires.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | TRI-BUILT |
| Manufacturer model | TB-316920 |
| Sell unit | 1 board, 4 ft. x 8 ft. x 2.6 in. |
| Product line | TRI-BUILT ISO Rigid Roof Insulation |
| Material | Polyisocyanurate (polyiso) rigid foam |
| Nominal size | 4 ft. x 8 ft. |
| Thickness | 2.6 in. |
| Coverage per unit | 32 sq ft per board |
| Weight | 14.75 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 of roof area. Divide your total roof area by 32 to estimate board count, allowing for edge fit and cut waste.
Fit and Compatibility:
TRI-BUILT ISO boards are used as rigid insulation within low-slope roof assemblies and pair with roof cover boards, insulation adhesives and single-ply or modified bitumen membranes. Fastening pattern and attachment method should follow the roofing system manufacturer's requirements.
Frequently Asked Questions (FAQ):
Q: What is included in one order?
A: One 2.6 in. thick, 4 ft. x 8 ft. polyiso insulation board, sold as a single piece.
Q: How many boards do I need?
A: Each board covers 32 sq ft, so divide your roof area in square feet by 32 and add for cuts and waste.
Q: How is the board installed?
A: Rigid polyiso is typically mechanically fastened or adhered per the roofing system manufacturer's instructions; follow local code for attachment.
Q: Can I use this under any membrane?
A: It is intended as rigid insulation in low-slope assemblies; confirm acceptance with your membrane system manufacturer before installation.
Q: How much does one board weigh?
A: Approximately 14.75 lb per board.
Q: Is it cut on site?
A: Yes, rigid polyiso boards can be scored and cut to fit with a common insulation saw or utility knife.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
Polyiso is the standard choice for low-slope roof insulation because of its high R-value per inch; a 2.6 in. board lets you build thickness in fewer layers. Stage boards flat and keep them dry until covered, and stagger joints between layers when installing multiple lifts. Verify attachment requirements with the membrane manufacturer and local wind-uplift code.
Wear gloves, eye protection and a dust mask when cutting rigid foam boards, and follow the roofing system manufacturer's instructions and local code.
Order TRI-BUILT 2.6 in. ISO rigid roof insulation boards today and build your roof assembly in fewer layers.
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