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SOPREMA Sopra ISO Polyiso Roof Insulation Board, 4 ft x 8 ft, 3 in. or 4 in.
Regular price $81.25Orders start at $399 — combine any items to reach the minimum. Learn more
SOPREMA Sopra ISO Polyiso Roof Insulation Board, 4 ft x 8 ft, 3 in. or 4 in.
Soprema Sopra ISO is a flat polyisocyanurate roof insulation board supplied in 4 ft x 8 ft sheets, available in 3 in. and 4 in. thicknesses. Each sheet is sold per piece and serves as the insulation layer in Soprema commercial low-slope roof assemblies, installed under the membrane with approved fasteners and plates.
Key Features:
- Flat ISO board: Manufactured as flat ISO insulation for low-slope commercial roof assemblies.
- Full 4 x 8 sheet: Each board measures 4 ft x 8 ft, giving 32 sq ft of coverage per sheet.
- Two thicknesses: Offered in 3 in. and 4 in. thicknesses to meet project R-value and assembly requirements.
- System fit: Designed to work within Soprema's commercial roofing membrane systems.
- Per-piece ordering: Sold by the piece, so you can order exactly the number of sheets your roof area requires.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | Soprema |
| Sell unit | 1 piece, 4 ft x 8 ft |
| Product line | Sopra ISO |
| Available sizes | 3 in. x 4 ft x 8 ft; 4 in. x 4 ft x 8 ft |
| Dimensions | 4 ft x 8 ft board |
| Nominal size | 3 in. or 4 in. thickness |
| Material | Polyisocyanurate (flat ISO) insulation |
| Coverage per unit | 32 sq ft per 4 ft x 8 ft sheet |
| Intended use | Insulation layer in commercial low-slope roofing assemblies |
Coverage & How Much You Need:
Each 4 ft x 8 ft sheet covers 32 sq ft. Divide the total roof area by 32 to estimate sheets, then add 5-10% for cuts, waste and perimeter fit, and plan board layout so end joints are staggered between rows.
Fit and Compatibility:
Use under Soprema SBS-modified bitumen, PMMA liquid-applied or single-ply PVC membrane systems with approved insulation fasteners and plates. Confirm the membrane system's approved insulation and attachment requirements before substituting other boards.
Frequently Asked Questions (FAQ):
Q: What sizes are available?
A: The line is offered in 3 in. and 4 in. thicknesses, both in a 4 ft x 8 ft sheet.
Q: How much does one sheet cover?
A: A 4 ft x 8 ft sheet covers 32 sq ft of roof area before waste allowance.
Q: How is it attached?
A: Flat ISO board is typically mechanically attached with insulation fasteners and plates; use approved Soprema HD fasteners and follow the specified fastening density.
Q: Can it be used under any membrane?
A: It is intended for Soprema commercial roofing assemblies; verify compatibility with your specific membrane system before ordering.
Q: How do I calculate my order?
A: Divide roof area by 32 sq ft per sheet, then add waste for perimeter cuts and staggered joints.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
Polyiso is the standard choice for commercial low-slope roofs when you need high R-value per inch; pick 4 in. over 3 in. where the project's total R-value target demands it or to reduce layer count. Store sheets off the ground and under cover until install day, and stagger board joints between rows. Order the matching fastener length for the board thickness plus deck penetration. Confirm the system specification allows flat ISO in the given thickness before substitution.
Handle boards with care on the roof and keep insulation dry before covering; do not install over a wet or damaged deck.
Get Soprema Sopra ISO polyiso insulation in 3 in. or 4 in. for your next commercial roof.
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