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CertainTeed FlintBoard Flat ISO Polyisocyanurate Roof Insulation, 2.6 in. x 4 ft. x 8 ft. Panel
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CertainTeed FlintBoard Flat ISO Polyisocyanurate Roof Insulation, 2.6 in. x 4 ft. x 8 ft. Panel
CertainTeed FlintBoard Flat ISO is a polyisocyanurate roof insulation panel with a closed-cell polyiso core laminated to heavy, black, fiber-reinforced felt facers. This 2.6 in. x 4 ft. x 8 ft. panel is approved under built-up, modified bitumen and single-ply roof systems, and is the recommended insulation for CertainTeed commercial roofing systems including Flintlastic. Sold as a single panel.
Key Features:
- Closed-cell polyiso core: FlintBoard ISO features a closed-cell polyisocyanurate core integrally laminated to heavy, black (non-asphaltic), fiber-reinforced felt facers.
- Universal facers: Marked on one side for hot-applied systems and unmarked on the opposite side for single-ply use, making it universally adaptable.
- Works under any membrane: Approved for use under all major roof covering systems: built-up, modified bitumen and single ply.
- High thermal resistance: The line is offered in a variety of thicknesses providing LTTR values from 6.0 to 25.0.
- Strength options: Also available in a 25-psi formula in addition to the standard 20-psi grade.
- Code listed: Meets or exceeds ASTM C1289, Type II, Class 1, Grade 2 (20 psi) or Grade 3 (25 psi), IBC Chapter 26, Florida Product Approval FL5968, and California Title 24.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | CertainTeed |
| Sell unit | 1 panel, 2.6 in. x 4 ft. x 8 ft. |
| Product line | FlintBoard Flat ISO |
| Material | Polyisocyanurate (polyiso) closed-cell foam with fiber-reinforced felt facers |
| Color / finish | Brown |
| Dimensions | 2.6" x 4' x 8' |
| Available sizes | 4' x 4' and 4' x 8' panels in a variety of thicknesses (LTTR 6.0 to 25.0) |
| Facers | Heavy, black (non-asphaltic), fiber-reinforced felt |
| Approvals | ASTM C1289 Type II, Class 1, Grade 2 (20 psi) or Grade 3 (25 psi); IBC Chapter 26; Florida Product Approval FL5968; California Code of Regulations Title 24; insulation quality standard licensed |
| Compressive strength options | 20 psi grade or 25-psi formula |
| Intended use | Roof insulation under built-up, modified bitumen and single-ply systems |
| System pairing | Recommended insulation with CertainTeed Commercial Roofing Systems, including Flintlastic Roof Systems |
Coverage & How Much You Need:
One 4 ft. x 8 ft. panel covers 32 sq ft of roof area; the listed 2.6 in. thickness provides the LTTR value for that thickness in the FlintBoard line. Divide total roof area by 32 sq ft per panel to size the insulation order, accounting for layout and taper needs.
Fit and Compatibility:
Installs under built-up, modified bitumen and single-ply coverings, and is the recommended insulation for CertainTeed Commercial Roofing Systems including Flintlastic Roof Systems. The marked side is designated for hot-applied systems and the unmarked side for single-ply; mechanical fasteners or adhesives for attachment are sold separately.
Frequently Asked Questions (FAQ):
Q: What is included?
A: One CertainTeed FlintBoard Flat ISO insulation panel, 2.6 in. thick x 4 ft. x 8 ft., with black fiber-reinforced felt facers.
Q: What roof systems can it go under?
A: It is approved under all major roof covering systems: built-up, modified bitumen and single ply.
Q: Which side goes up?
A: One side is marked for use with hot-applied systems; the unmarked opposite side is for single-ply systems.
Q: What strength is available?
A: This panel is the standard grade (Grade 2, 20 psi per ASTM C1289); the line is also available in a 25-psi formula.
Q: How much area does one panel cover?
A: A 4 ft. x 8 ft. panel covers 32 sq ft; calculate your roof area and divide by 32 to estimate panel count.
Q: Is it code approved?
A: It meets or exceeds ASTM C1289 Type II Class 1, IBC Chapter 26, Florida Product Approval FL5968 and California Title 24.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
FlintBoard Flat ISO is a dependable coverboard and primary insulation for commercial assemblies; the dual-sided facers let one stock item serve both hot-applied and single-ply crews. Step the joints and layer across the deck for a smooth substrate. For higher-load applications, specify the 25-psi formula rather than the standard grade.
Polyiso insulation boards are combustible and must be protected by the finished roof assembly; store panels away from ignition sources and follow local fire codes.
Order CertainTeed FlintBoard Flat ISO 2.6 in. polyiso roof insulation for your next commercial roof.
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