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TRI-BUILT 2 in. x 4 ft. x 8 ft. ISO Rigid Roof Insulation Board
Regular price $45.36Orders start at $399 — combine any items to reach the minimum. Learn more
TRI-BUILT 2 in. x 4 ft. x 8 ft. ISO Rigid Roof Insulation Board
This is a single TRI-BUILT 2.0 in. thick, 4 ft. x 8 ft. polyiso (ISO) rigid roof insulation board, sold per piece and weighing about 12.16 lb. The thicker board delivers more thermal resistance per layer in low-slope roofing assemblies. Count boards from your roof area and the R-value target of your roof system design.
Key Features:
- Polyiso core: Rigid polyisocyanurate insulation board, listed as Polyiso.
- 2 in. thickness: 2.0 in. board thickness for greater thermal resistance per layer.
- 4 x 8 board: Standard 4 ft. x 8 ft. board size for flat-roof coverage.
- Manageable weight: About 12.16 lb per 2 in. board for roof-top handling.
- Low-slope use: Rigid insulation for low-slope roofing assemblies.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | TRI-BUILT |
| Manufacturer model | TB-316825 |
| Sell unit | 1 board, 4 ft. x 8 ft. x 2.0 in. |
| Product line | ISO Rigid Roof Insulation |
| Material | Polyisocyanurate (polyiso) |
| Thickness | 2.0 in. |
| Dimensions | 4 ft. x 8 ft. |
| Board size | 48 in. x 96 in. |
| Coverage per unit | 32 sq ft per board |
| Weight | 12.16 lb per board |
| QXO category | Polyiso |
| Intended use | Rigid 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 sq ft per board and plan staggered joints between layers; the 2 in. thickness reduces board count versus 1 in. for the same R-value.
Fit and Compatibility:
For low-slope roof assemblies under approved membrane systems per the roofing manufacturer's requirements. Boards sold individually; adhesives, fasteners/plates, cover boards and membranes are sold separately. R-value per inch is not stated in the sources.
Frequently Asked Questions (FAQ):
Q: What size is each board?
A: Each board is 4 ft. x 8 ft. (48 in. x 96 in.) and 2.0 in. thick.
Q: How much does one board cover?
A: One board covers 32 sq ft of roof area, before waste and joint allowance.
Q: How is it sold?
A: Sold per piece, one board per order unit.
Q: What material is it?
A: Polyisocyanurate (polyiso) rigid foam, listed under the Polyiso category.
Q: Why choose 2 in. over 1 in.?
A: The 2 in. board gives more R-value per layer, reducing board count and joint lines in thicker assemblies.
Q: How much does it weigh?
A: About 12.16 lb per 2 in. board.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
Use 2 in. boards when a single thicker layer meets the R-value target, or as the upper layer over 1 in. boards with joints staggered. Confirm membrane adhesive compatibility with polyiso facers and verify fastener/plate lengths for the doubled assembly thickness.
Handle boards carefully on windy roofs and install per the roofing system manufacturer's instructions and local building code.
Order TRI-BUILT 2 in. 4x8 polyiso rigid roof insulation boards for higher R-value in fewer layers.
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