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IKO IKOTherm Grade-II (20 psi) Polyiso Roof Insulation Board, 4 in. x 4 ft. x 8 ft.
Regular price $62.00Orders start at $399 — combine any items to reach the minimum. Learn more
IKO IKOTherm Grade-II (20 psi) Polyiso Roof Insulation Board, 4 in. x 4 ft. x 8 ft.
This IKO IKOTherm Grade-II polyisocyanurate roof insulation board measures 4 in. thick, 4 ft. x 8 ft., and is rated 20 psi compressive strength (Grade-II). It uses a kraft paper facer reinforced with glass fiber strands for high strength and strong adhesive or hot-mop absorption. Sold per piece; 9 boards cover one roofing square (100 sq ft).
Key Features:
- Broad system use: Designed to be part of modified bitumen, built-up, or single-ply roof systems.
- High R-value per inch: Rigid polyiso foam with high thermal properties helps reduce heating and cooling costs.
- Grade-II 20 psi: Grade-II compressive strength rated at 20 psi for low-slope roof assemblies.
- Adhesion-ready facer: Kraft paper reinforced with fiberglass strands offers excellent absorption for hot mopping and adhesive attachment.
- Mechanical fastening: Also performs well when installed with mechanical fasteners.
- Lightweight handling: Lightweight boards are easy to handle and carry on the roof.
- Code-listed: Meets ASTM C1289 and CAN/ULC S-704, with FM Approval and UL Classification.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | IKO |
| Manufacturer model | 4183133 |
| Sell unit | 1 board, 4 in. x 4 ft. x 8 ft. |
| Product line | IKOTherm polyisocyanurate roof insulation |
| Profile / style | Flat board, kraft/fiberglass-reinforced facers |
| Color | Tan |
| Dimensions | 4 ft x 8 ft x 4 in. thick |
| Coverage per unit | 32 sq ft per board |
| Material | Polyisocyanurate foam, kraft paper facer reinforced with glass fiber strands |
| Compressive strength | 20 psi (Grade-II) |
| Applicable standards | ASTM C1289; CAN/ULC S-704; FM Approved; UL Classified |
| Weight | 21 lb per board |
| Algae resistance | No |
| Intended use | Modified bitumen, built-up, or single-ply low-slope roof insulation |
Coverage & How Much You Need:
One 4 ft x 8 ft board covers 32 sq ft of roof deck. Three boards give 96 sq ft, so allow 9 boards per roofing square (288 sq ft) to cover 100 sq ft with staggered joints and cuts.
Fit and Compatibility:
Made for modified bitumen, built-up and single-ply low-slope roof systems; install over decks and under membranes per IKO and system manufacturer specifications. Attachment adhesives, hot mop, mechanical fasteners and other thicknesses are sold separately.
Frequently Asked Questions (FAQ):
Q: How many boards do I need for one square?
A: Each 4 ft x 8 ft board covers 32 sq ft; plan on 9 boards (288 sq ft) per 100 sq ft square to account for cuts and joint stagger.
Q: Can it be hot mopped?
A: Yes. The fiberglass-reinforced kraft facer is designed with excellent absorption for both hot mopping and adhesive attachment, and also works with mechanical fasteners.
Q: What compressive strength is Grade-II?
A: Grade-II is a 20 psi compressive-strength rating per the ASTM C1289 classification.
Q: Which roof systems is it used in?
A: IKOTherm is designed to be part of modified bitumen, built-up, or single-ply roof systems.
Q: What size is each board?
A: This item is a 4 in. thick, 4 ft x 8 ft board; IKOTherm is also offered in other sizes and thicknesses, sold separately.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
The 4 in. x 4 ft x 8 ft board is efficient for large decks, giving 32 sq ft per piece with fewer joints than 4x4 boards. For BUR and modified bitumen, the absorption-friendly kraft facer suits hot mop and adhesive attachment; for single-ply, stagger two layers and verify fastener density for uplift. Confirm the aged/LTTR R-value from the board label for code compliance.
Hot mopping and adhesive application require proper PPE and fire precautions; follow the membrane manufacturer's instructions and local code.
Order the IKO IKOTherm 4 in. polyiso roof insulation board for efficient, high R-value coverage.
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