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Carlisle SynTec InsulBase 2.2 in. x 4 ft x 8 ft Polyiso Roof Insulation Panel, Grade II (20 psi)
Regular price $39.25Orders start at $399 — combine any items to reach the minimum. Learn more
Carlisle SynTec InsulBase 2.2 in. x 4 ft x 8 ft Polyiso Roof Insulation Panel, Grade II (20 psi)
This is a Carlisle SynTec InsulBase Grade-II polyiso roof insulation panel, 2.2 in. thick and 4 ft x 8 ft, with a closed-cell polyisocyanurate foam core bonded to glass-reinforced felt (GRF) facers on both sides. One panel is one sell unit, covering 32 sq ft, and it installs under Carlisle single-ply membrane systems with adhesive or mechanical attachment.
Key Features:
- High R-Value: InsulBase polyiso provides the highest R-value per inch of commercially available insulation products.
- ReadyFlash Facer: ReadyFlash Technology pairs a dark GRF facer that accelerates adhesive flash-off with a light GRF facer that slows it.
- Steel Deck Rated: Approved for direct application to steel decks.
- Grade II 20 psi: Meets ASTM C1289, Type II, Class 1, Grade 2 (20 psi compressive resistance).
- Broad Approvals: UL Classified, FM Class 1 approved (4450/4470), Florida Building Code approved, and IBC Section 2603 compliant.
- Environmentally Friendly: Zero ozone-depleting components with an HFC- and HCFC-free formulation.
- Green Building Ready: CDPH compliant and contributes to LEED certification requirements.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | Carlisle SynTec |
| Manufacturer model | 323401 |
| Sell unit | 1 panel, 4 ft x 8 ft x 2.2 in. |
| Product line | InsulBase |
| Material | Closed-cell polyisocyanurate foam with glass-reinforced felt (GRF) facers |
| Color | Tan |
| Dimensions | 4 ft x 8 ft, 2.2 in. thick |
| Thickness | 2.2 in. |
| Compressive strength | Grade 2 (20 psi) |
| Coverage per unit | 32 sq ft per panel |
| Standards | ASTM C1289, Type II, Class 1, Grade 2; IBC Section 2603; UL 790, 263, 1256; FM 4450/4470 Class 1; CAN/ULC S704 Type 2 & 3, Class 3 |
| Certifications | PIMA Quality Mark, CDPH compliant, LEED, Florida Building Code approved, California Title 24 |
| Weight | 14.528 lb per panel |
Coverage & How Much You Need:
Each 4 ft x 8 ft panel covers 32 square feet of roof deck; divide total roof area by 32 to size panel quantities.
Fit and Compatibility:
Part of the Carlisle SynTec commercial roofing system and pairs with Carlisle single-ply membranes, adhesives and fasteners (sold separately). InsulBase is designed for low-slope commercial roof assemblies over steel decks.
Frequently Asked Questions (FAQ):
Q: What is included in one order?
A: One 2.2 in. x 4 ft x 8 ft InsulBase Grade-II polyiso insulation panel.
Q: How much area does one panel cover?
A: A 4 ft x 8 ft panel covers 32 square feet of deck area.
Q: What is ReadyFlash Technology?
A: The board has a dark GRF facer on one side and a light GRF facer on the other; applying membrane adhesive to the dark side speeds adhesive flash-off, while the light side slows it.
Q: Can this be applied directly to a steel deck?
A: Yes, InsulBase polyiso is approved for direct application to steel decks.
Q: What compressive strength does this panel have?
A: It is a Grade 2 panel rated to 20 psi compressive resistance per ASTM C1289.
Q: What thickness is this item?
A: This item is the 2.2 in. thickness; other InsulBase thicknesses are separate items.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
InsulBase is Carlisle's workhorse flat polyiso, and the 2.2 in. thickness gives strong thermal performance per board while keeping panel count manageable. Use the dark GRF facer up on cool days and the light facer up in heat to control membrane adhesive flash-off times. Confirm LTTR values and fastening patterns against Carlisle's data sheets and local code before ordering; cover board is often specified over insulation in high-traffic or hail-exposed assemblies.
Handle rigid foam panels carefully at edges and corners, and follow the manufacturer's installation instructions and local building code for attachment and fire requirements.
Order the Carlisle SynTec InsulBase 2.2 in. polyiso panel for your commercial roofing project today.
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