GAF EnergyGuard 1.5 in. x 4 ft. x 8 ft. Grade-II (20 psi) Polyiso Roof Insulation Panel

This is a GAF EnergyGuard 1.5 in. polyisocyanurate roof insulation panel, 4 ft x 8 ft, Grade-II (20 psi) with glass fiber reinforced cellulosic felt facers bonded to a polyiso foam core. Each panel provides 32 sq ft of coverage and ships as a single piece. It pairs with GAF single-ply, mod bit and BUR roof systems, including tapered designs.

Key Features:

• High thermal value: Polyisocyanurate foam core with glass fiber reinforced cellulosic felt facers delivers high thermal efficiency for low-slope roofs.
• 20 psi compressive strength: ASTM C1289 Type II, Class 1 Grade 2 rating provides 20 psi compressive strength.
• System approvals: Approved for use in mod bit, BUR and single-ply systems with FM 4450/4470 and UL listings.
• Membrane compatible: Compatible with TPO and PVC membranes in adhered, mechanically attached and induction welded systems.
• Easy handling: Lightweight panels are easy to cut in the field for faster installation.
• Taper-ready design: Suitable for tapered design systems that help drive water to drains and reduce ponding.
• Green building credit: Green Circle Certified for recycled content and contributes to green building rating systems.

Specifications Table:

Coverage & How Much You Need:

One panel covers 32 sq ft (4 ft x 8 ft). Bundles of 32 pieces cover 1024 sq ft, so a 1,000 sq ft roof area needs roughly 32 panels. In tapered systems, panel count and slope layout should follow a tapered design plan.

Fit and Compatibility:

Compatible with GAF single-ply (TPO and PVC), modified bitumen and BUR roof systems in adhered, mechanically attached and induction welded applications. Membrane, adhesives and fasteners are sold separately; a cover board is required for UL Class A over combustible decks.

Frequently Asked Questions (FAQ):

Q: What is included in this order?
A: One 1.5 in. thick, 4 ft x 8 ft EnergyGuard Grade-II (20 psi) polyiso insulation panel. Bundles ship 32 pieces covering 1024 sq ft.

Q: How much area does one panel cover?
A: Each panel covers 32 sq ft; a full 32-piece bundle covers 1024 sq ft.

Q: Which membrane systems is it compatible with?
A: It is approved for mod bit, BUR and single-ply systems, and works with TPO and PVC in adhered, mechanically attached and induction welded assemblies.

Q: What is the compressive strength?
A: This panel is ASTM C1289 Type II, Class 1 Grade 2, rated at 20 psi.

Q: Is a cover board required?
A: For UL Class A over combustible decks, a cover board is required per GAF's listing notes.

Q: Is this a flat or tapered panel?
A: This item is a flat polyiso panel; GAF's EnergyGuard tapered line is available in slopes from 1/16 in. to 1/2 in. per foot for drainage designs.

Expert Verdict — Reviewed by the SuperArbor Pro Desk

Polyiso is the go-to choice for R-value per inch on commercial low-slope roofs, and this 1.5 in. Grade-II panel suits most standard adhered and mechanically attached assemblies. Stack layers with staggered joints, and use GAF-approved adhesives or fasteners per the membrane manufacturer's instructions. For roofs with ponding issues, combine flat panels like this with EnergyGuard tapered panels or crickets to establish positive drainage.

Install per GAF's instructions and local building code, and use fall protection when working on low-slope roofs.

Order the GAF EnergyGuard 1.5 in. polyiso roof insulation panel for your next low-slope roofing project.