TRI-BUILT 1 in. x 4 ft. x 8 ft. ISO Rigid Roof Insulation Board

This is a single TRI-BUILT 1.0 in. thick, 4 ft. x 8 ft. polyiso (ISO) rigid roof insulation board, sold per piece and weighing about 7.84 lb. Polyiso boards are installed as insulation in low-slope roofing assemblies, typically under or over the membrane per the roof system design. Layer thickness and board count should follow your roof system’s R-value requirement.

Key Features:

• Polyiso core: Rigid polyisocyanurate insulation board, categorized as Polyiso in the listing.
• 1 in. thickness: 1.0 in. board thickness for this item.
• 4 x 8 board: Standard 4 ft. x 8 ft. board dimensions for efficient flat-roof coverage.
• Lightweight board: About 7.84 lb per 1 in. board for easy handling on the roof.
• Low-slope use: Rigid roof insulation intended for low-slope roof assemblies.

Specifications Table:

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, allowing for joints and layering, to size your order; stagger board joints between layers.

Fit and Compatibility:

Use within low-slope roof assemblies under approved membrane systems per the roofing manufacturer’s requirements. Boards are 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 1.0 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 are boards sold?
A: Sold per piece; order one board at a time as needed.

Q: What material is it?
A: Polyisocyanurate (polyiso) rigid foam insulation, listed under the Polyiso category.

Q: How is it installed?
A: Install per your roof system manufacturer’s instructions, typically adhered or mechanically fastened; follow local code.

Q: How much does it weigh?
A: About 7.84 lb per 1 in. board.

Expert Verdict Reviewed by the SuperArbor Pro Desk

Stagger joints between successive layers and cut boards to fit perimeters tight to avoid thermal bridges. On fully adhered systems, verify the membrane adhesive is compatible with polyiso facers. For higher R-value targets, layer multiple thicknesses in this series rather than relying on a single 1 in. layer.

Handle boards carefully on windy roofs and follow the roofing system manufacturer’s instructions and local building code for insulation attachment.

Order TRI-BUILT 1 in. 4×8 polyiso rigid roof insulation boards to build up your low-slope roof assembly.