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Atlas ACFoam-II 1 in. x 4 ft. x 4 ft. Polyiso Roof Insulation Board, Grade-II (20 psi)
Regular price $14.10Orders start at $399 — combine any items to reach the minimum. Learn more
Atlas ACFoam-II 1 in. x 4 ft. x 4 ft. Polyiso Roof Insulation Board, Grade-II (20 psi)
This is Atlas ACFoam-II polyiso roof insulation, 1 in. thick, 4 ft. x 4 ft. panel, Grade-II (20 psi) flat board. Each panel covers 16 sq ft and is sold per piece. It is used as roof insulation under membrane and other low-slope coverings, alone or layered for higher R-value.
Key Features:
- 1 in. polyiso board: 1 in. thick polyisocyanurate roof insulation panel.
- 4 x 4 ft. panel: Each panel measures 4 ft. x 4 ft., covering 16 sq ft.
- 20 psi Grade II: Manufactured to ASTM C1289 Type II, Class 1, Grade 2 (20 psi).
- Low-GWP foam: Made with CFC-free, HCFC-free and HFC-free blowing agents with zero ODP and negligible GWP.
- Recycled content: Contains between 52.9% and 27.6% recycled materials per the manufacturer.
- Broad approvals: FM 4450/4470 approved, Miami-Dade County and Florida Product Approved, UL Greenguard Gold certified.
- Code compliance: Meets ASTM C1289 and CAN/ULC-S704; IBC Chapter 26 and NBC recognized.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | Atlas |
| Manufacturer model | AC2_003 |
| Sell unit | 1 panel, 1 in. x 4 ft. x 4 ft. (16 sq ft) |
| Product line | ACFoam-II flat polyiso |
| Dimensions | 1 in. x 4 ft. x 4 ft. |
| Compressive strength | Grade 2 (20 psi) per ASTM C1289 Type II, Class 1 |
| Coverage per unit | 16 sq ft per panel |
| Material | Polyisocyanurate foam (facers as manufactured) |
| Color | Brown |
| Approvals | ASTM C1289; CAN/ULC-S704; CCMC No. 12464-L; UL 1256; UL 790 (ASTM E108); UL 263 (ASTM E119); UL 1897; FM 4450/4470 Approved; Miami-Dade County Approved; Florida Product Approved; UL Greenguard Gold Certified |
| Foam technology | CFC-free, HCFC-free, HFC-free blowing agents; zero ODP, negligible GWP |
| Weight | 5 lb per panel |
| Intended use | Low-slope roof insulation under membrane roof systems |
Coverage & How Much You Need:
Each 4 ft. x 4 ft. panel covers 16 sq ft. Divide the roof area by 16 and add waste and taper requirements; layer multiple thicknesses or use thicker panels to reach the target R-value.
Fit and Compatibility:
Designed for low-slope membrane roof assemblies; install over compatible decks and thermal barriers and beneath single-ply, modified bitumen or built-up membranes per the membrane manufacturer's requirements. Attachment fasteners, plates and cover boards are sold separately.
Frequently Asked Questions (FAQ):
Q: What are the panel dimensions?
A: 1 in. thick, 4 ft. x 4 ft., covering 16 sq ft per panel.
Q: What grade is this board?
A: Grade-II, 20 psi compressive strength per ASTM C1289 Type II, Class 1.
Q: Is it environmentally specified?
A: It uses CFC-free, HCFC-free and HFC-free blowing agents with zero ODP and negligible GWP, and contains recycled material.
Q: Is it FM approved?
A: Yes, it is FM Standard 4450/4470 approved and also Miami-Dade County and Florida Product Approved.
Q: How many panels for 1,000 sq ft?
A: About 63 panels (1,000 divided by 16 sq ft each), plus waste and cut pieces.
Q: How much does one panel weigh?
A: The listed item weight is 5 lb.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
ACFoam-II in 4 x 4 ft. panels is handy for small roofs, patch-ins and detailing where 4 x 8 boards are awkward. Check your spec for Grade 2 (20 psi) versus Grade 3 (25 psi) and the required R-value before ordering—1 in. panels are often layered. Follow Atlas's recommendation to confirm local code, FM Global, Miami-Dade and membrane manufacturer requirements before installation.
Consult local building codes, contract documents, the membrane manufacturer and a design professional for installation guidelines, and follow the roofing system's fire and wind uplift requirements.
Order Atlas ACFoam-II 1 in. x 4 ft. x 4 ft. polyiso roof insulation for your low-slope roof assembly.
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