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GAF EnergyGuard 3 in. 4 ft x 8 ft Grade-II (20 psi) Polyiso Roof Insulation Panel
Regular price $72.14Orders start at $399 — combine any items to reach the minimum. Learn more
GAF EnergyGuard 3 in. 4 ft x 8 ft Grade-II (20 psi) Polyiso Roof Insulation Panel
This is a GAF EnergyGuard 3 in. thick polyisocyanurate roof insulation panel measuring 4 ft x 8 ft, rated Grade-II (20 psi) under ASTM C1289 Type II. Each panel is a sell unit sold by the piece; a bundle contains 16 panels covering 512 sq ft. It pairs with GAF-approved low-slope roof systems including single-ply, mod bit and BUR assemblies.
Key Features:
- High thermal value: A 3 in. polyiso core bonded to glass fiber reinforced cellulosic felt (GRF) facers delivers high thermal efficiency.
- 20 psi compressive strength: Grade-II rating per ASTM C1289 Type II, Class 1 provides 20 psi compressive strength for commercial low-slope roofing.
- Fewer seams per square: The 4 ft x 8 ft format covers 32 sq ft per panel, reducing joints and installation labor versus smaller boards.
- Wide system compatibility: Approved for use with modified bitumen, BUR and single-ply systems, including TPO and PVC in adhered, mechanically attached and induction welded applications.
- Broad approvals: FM Approved, UL Classified, Miami-Dade County Approved and Florida Building Code Approved.
- Easy field cutting: Lightweight panels are easy to cut in the field, making handling and installation more efficient.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | GAF |
| Sell unit | 1 panel, 4 ft x 8 ft x 3 in. |
| Product line | EnergyGuard Polyiso Roof Insulation |
| Material | Polyisocyanurate foam core with glass fiber reinforced cellulosic felt (GRF) facers |
| Dimensions | 4 ft x 8 ft, 3 in. thick |
| Thickness | 3 in. |
| Compressive strength | 20 psi (Grade-II) |
| Standard | ASTM C1289, Type II (Class 1); ASTM D1621; ASTM D2126; ASTM C209; ASTM E96; ASTM E84 |
| Approvals | FM Approved; UL Classified; Florida Building Code Approved; Miami-Dade County Approved; PIMA Quality Mark |
| Pack quantity | 16 pieces per bundle |
| Coverage per unit | 512 sq ft per bundle (32 sq ft per panel) |
| Weight | 18.688 lb per panel |
| Intended use | Commercial low-slope roof insulation |
Coverage & How Much You Need:
One 4 ft x 8 ft panel covers 32 sq ft; a full bundle of 16 panels covers 512 sq ft. Divide the roof area by 32 sq ft per panel to estimate panel count.
Fit and Compatibility:
Approved for modified bitumen, BUR and single-ply roof systems, including TPO and PVC in adhered, mechanically attached and induction welded systems. Membrane, adhesive and fastening components are sold separately; install per GAF specification.
Frequently Asked Questions (FAQ):
Q: What is included in one order?
A: One 4 ft x 8 ft, 3 in. thick polyiso insulation panel; panels ship 16 per bundle.
Q: How many panels do I need?
A: Each panel covers 32 sq ft, so divide your roof area by 32 to estimate the panel count and allow for cuts.
Q: What strength is this panel?
A: It is Grade-II per ASTM C1289 Type II, Class 1, rated at 20 psi compressive strength.
Q: Can it be used under TPO or PVC membranes?
A: Yes, GAF lists compatibility with TPO and PVC in adhered, mechanically attached and induction welded single-ply systems, plus mod bit and BUR.
Q: Is it approved in my region?
A: It is FM Approved, UL Classified, Florida Building Code Approved and Miami-Dade County Approved; always confirm with local code requirements.
Q: How heavy are the panels?
A: Each 3 in. 4x8 panel weighs about 18.7 lb; plan for two-person handling.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
The 4x8 format installs faster than 4x4 boards because it covers 32 sq ft per panel with fewer seams to stagger and tape. Use 3 in. boards as the main body layer when R-value targets call for thick polyiso, and verify fastener lengths reach the deck. Pair with a GAF-approved cover board where UL Class A over combustible decks is required.
Handle and cut panels with gloves and eye protection, and follow the manufacturer's installation instructions and local building code for attachment and fire-assembly requirements.
Order GAF EnergyGuard 3 in. 4x8 polyiso roof insulation today for faster coverage with fewer seams.
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