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InsulFoam C8 Tapered EPS 4 ft. x 8 ft. Roof Insulation Board, 1.25 pcf Density
Regular price $170.31Orders start at $399 — combine any items to reach the minimum. Learn more
InsulFoam C8 Tapered EPS 4 ft. x 8 ft. Roof Insulation Board, 1.25 pcf Density
This is InsulFoam C8 tapered expanded polystyrene (EPS) roof insulation in 4 ft. x 8 ft. boards with a 1.25 pcf density. Tapered boards are used to build slope and drainage into low-slope roof assemblies. Bundles contain 6 pieces; each order unit is one piece.
Key Features:
- Tapered for Drainage: Tapered EPS board profile creates positive slope and drainage in low-slope roof systems.
- 1.25 pcf Density: Manufactured at 1.25 pounds per cubic foot density on this item.
- 4 x 8 Board: Standard 4 ft. x 8 ft. board size for efficient layout and coverage.
- ASTM C578: Meets ASTM C578, the standard specification for EPS roof insulation.
- Wide Approvals: UL Approved, FM Approved, Miami-Dade County and ICC-ES Approved as listed.
- Green Building: Energy Star, NAHB National Green Building Program and USGBC membership listed.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | InsulFoam |
| Sell unit | 1 board, 4 ft. x 8 ft. (bundles of 6) |
| Product line | InsulFoam C8 |
| Profile / style | Tapered EPS roof insulation board |
| Dimensions | 4 ft. x 8 ft. board, tapered profile |
| Density | 1.25 pcf |
| Pack quantity | 6 pieces per bundle |
| Material | Expanded polystyrene (EPS) |
| Approvals | ASTM C578; Energy Star; U.S. Green Building Council Member; UL Approved; FM Approved; Miami-Dade County; ICC-ES Approved; NAHB National Green Building Program |
| Intended use | Tapered roof insulation for low-slope roofing assemblies |
| Product weight, complete sell unit | 1 lb |
Coverage & How Much You Need:
Each 4 ft. x 8 ft. board covers 32 sq ft at the plan-view layout; tapered boards build slope across the roof, so the crickets and tapered layout determine total board counts. Work with the tapered insulation layout drawing to order the correct mix of slopes and thicknesses.
Fit and Compatibility:
Used in low-slope roof assemblies under approved membrane systems; coordinate thickness, slope and taper direction with the roof manufacturer's requirements. Cover boards and membrane adhesives are sold separately and must be compatible with EPS.
Frequently Asked Questions (FAQ):
Q: What is included in one order unit?
A: One piece of 4 ft. x 8 ft. tapered EPS board; bundles are packaged 6 pieces each.
Q: How much area does one board cover?
A: One 4 ft. x 8 ft. board covers 32 sq ft in plan view before accounting for tapered layout cuts.
Q: What does 1.25 pcf density mean?
A: It is the foam density of 1.25 pounds per cubic foot, which governs compressive performance of the board.
Q: What slope is this board?
A: The specific slope per inch and thickness range for this item are not printed in the listing; confirm the taper specification when ordering.
Q: Is it code approved?
A: It is listed as UL Approved, FM Approved, Miami-Dade County and ICC-ES Approved, and meets ASTM C578.
Q: Can it be installed directly under any membrane?
A: Membrane and adhesive compatibility with EPS must be confirmed with the roof system manufacturer before installation.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
Tapered EPS is an economical way to add slope and eliminate ponding on low-slope roofs; order from a tapered layout drawing so crickets at drains and valleys are built correctly. Because some hot asphalt and solvent-based adhesives are incompatible with EPS, verify adhesive type with the membrane manufacturer. Use a suitable cover board where membrane system requirements call for one.
Handle large foam boards carefully on windy rooftops to prevent loss or falls, and keep open flame and hot work away from EPS insulation.
Order InsulFoam C8 tapered EPS roof insulation today to build drainage into your low-slope roof.
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