1.5" 4x8 POLYISO FOIL SHEET R9.8
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1.5" x 4' x 8' Polyisocyanurate (Polyiso) Rigid Foam Insulation Board
Upgrade your building's thermal envelope with our high-performance 1.5-inch Polyiso Foil-Faced Insulation. Engineered for maximum efficiency, this rigid foam board delivers a superior R-value of 9.6 to 10.0 (industry standards for 1.5"), providing a powerful thermal break in a slim profile.
Note: While some specialized high-density or multi-layer products claim higher ratings, standard 1.5" Polyiso typically provides R-9.6. Please verify your specific project requirements.
Key Features
Superior Thermal Resistance: Offers the highest R-value per inch of any rigid foam insulation, significantly reducing energy costs.
Dual-Sided Foil Facer: Features a reflective foil facer on both sides. When installed with an air gap, it acts as a radiant barrier, reflecting up to 97% of radiant heat.
Moisture & Vapor Protection: The closed-cell structure and foil facers provide excellent water resistance and act as a built-in vapor retarder.
Versatile Application: Ideal for residential and commercial use, including masonry walls, framed walls, crawl spaces, and vaulted ceilings.
Easy Installation: Lightweight and easy to cut with a utility knife or saw. The 4' x 8' dimensions ensure rapid coverage of large areas.
Technical Specifications
| Feature | Specification |
|---|---|
| Thickness | 1.5 inches |
| Dimensions | 4 feet x 8 feet (32 sq. ft. per sheet) |
| Material | Closed-cell Polyisocyanurate foam core |
| Facer | Reflective Aluminum Foil (Both sides) |
| R-Value | R-9.6 (at 75°F mean temperature) |
| Fire Rating | Class A (typically meets ASTM E84) |
| Edge Profile | Square Edge |
Best Used For
Interior Walls: Continuous insulation to eliminate thermal bridging through studs.
Basements & Crawlspaces: High moisture resistance makes it perfect for below-grade interior applications.
Attics: Reflective surface helps keep homes cool in the summer and warm in the winter.
Exterior Sheathing: Provides a weather-resistant barrier when joints are taped.
Pro Tip: For maximum energy efficiency and moisture control, use Foil Seam Tape on all joints to create a continuous air and vapor seal.