GenFlex Roof Insulation & Cover Boards

Engineered for thermal performance and strength. Built for savings.

GenFlex^™ offers a curated portfolio of roofing insulation and cover board options designed to enhances thermal performance (R-value) while delivering a flat, stable surface and versatile product solutions. Our high-efficiency thermal insulation boards deliver exceptional reliability, impact resistance, energy savings, fire resistance and easy handling and installation.

Insulation and Cover Boards offer benefits for everyone:

FOR ROOFERS

Lightweight, easy-to-cut boards designed for fast, precise installation and long-term performance.

For Design Pros

High R-value per inch and proven fire resistance support code compliance and sustainable building design.

For Building Owners

Durable, energy-saving insulation that lowers heating and cooling costs for the life of the roof.

Insulation and Cover Boards

GL ISO

Versatile, high-efficiency polyiso insulation board designed for use with virtually all membrane roofing systems. Also available in tapered configurations to promote positive drainage and extend roof life.

CG ISO

Coated glass facer polyiso delivers enhanced protection, superior wind uplift performance and exceptional fire and mold resistance. Engineered for strength and stability, it offers a Class A fire rating and reliable performance across a wide range of roofing systems.

HD ISO

High-strength polyiso cover board featuring a closed-cell foam core and coated glass facers for exceptional thermal performance.

HD Comp

Dual-layer solution that combines a ½ in HD ISO cover board with GenFlex GL ISO polyiso insulation in one high-performing, energy-efficient panel.

NB ISO

Durable, nailable composite insulation board featuring a polyiso foam core laminated to a 7/16 in OSB surface and glass-reinforced mat facer.

Insulation Quick Reference Chart

ASTM C1289 [Definitions Based on ASTM C1289: Standard Specification for Faced Rigid Cellular Polyisocyanurate Thermal Insulation Board]

	GL ISO	CG ISO	HD ISO	NB ISO	HD Comp
Material Description	GL ISO Glass reinforced mat facers on both sides	CG ISO Coated, inorganic fiberglass facers on both sides	HD ISO Cover board with coated glass facers on both sides	NB ISO Polyiso foam core laminated to a 7/16" OSB on one side and a glass reinforced mat facer on the other side	HD Comp HD ISO board on one side with coated, inorganic fiberglass facers on the other side
Installation Options	GL ISO Insulation adhesive Mechanically attached Loose laid	CG ISO Insulation adhesive Mechanically attached Loose laid	HD ISO Insulation adhesive Mechanically attached Loose laid	NB ISO Insulation adhesive Mechanically attached Loose laid	HD Comp Insulation adhesive Mechanically attached Loose laid
Sizes	GL ISO 4 ft x 4 ft (1.22 m x 1.22 m) 4 ft x 8 ft (1.22 m x 2.43 m)	CG ISO 4 ft x 4 ft (1.22 m x 1.22 m) 4 ft x 8 ft (1.22 m x 2.43 m) flat or selected tapered	HD ISO 4 ft x 4 ft (1.22 m x 1.22 m) 4 ft x 8 ft (1.22 m x 2.43 m)	NB ISO 4 ft x 4 ft (1.22 m x 1.22 m) 4 ft x 8 ft (1.22 m x 2.43 m)	HD Comp 4 ft x 4 ft (1.22 m x 1.22 m) 4 ft x 8 ft (1.22 m x 2.43 m)
Thickness	GL ISO 1.5 in (38.1 mm) to 4.0 in (101.6 mm)	CG ISO 1 in (25.4 mm) min. to 4 in (101.6 mm), flat or selected tapered	HD ISO ½ in (12.7 mm)	NB ISO 1.5 in (38.1 mm) min. to 4 in (101.6 mm)	HD Comp 1.5 in (38.1 mm) min. to 4 in (101.6 mm)

Why Choose GenFlex Polyiso?

Our next-generation polyisocyanurate formulation surpasses the industry average thermal performance at lower mean temperatures by 40%. This performance meets the recommended and required ASTM C1289 thermal resistance specifications and ensures maximum thermal performance at all temperatures for your projects.

Great Cost Savings

With the highest R-value per inch in colder mean temperatures*, GenFlex Polyiso can potentially save thousands in HVAC** costs, making it a smart investment for your building.

Better Thermal Performance

GenFlex Polyiso delivers up to 40% better thermal performance in cold temperatures than the competition, making it the perfect choice for the varied climates across the United States.

Environmentally Friendly

The patented formulation of GenFlex Polyiso provides superior thermal performance at low temperatures, but also allows GenFlex to manufacture more environmentally responsible products, improving the EPDs of our polyiso insulation.

Polyiso Brochure

LTTR Reference Card

*The thermal performance of GenFlex Polyiso is up to 40% better than major competitors when tested by an independent third party in cold temperature 40°F (4°C) applications according to ASTM C1289 standards. The increased R-value per inch means better thermal performance from the same roofing systems using the same amount of insulation compared to leading competitive products on the market. **Potential savings are only estimates; actual performance attributes vary based on many factors, including specific building features like skylights, wall insulation and HVAC performance. Energy savings were estimated using an industry-recognized tool adjusting insulation thermal performance at 40°F (4°C) and applying it to the number of heating days. Consult with a competent mechanical engineer and/or roofing professional for more tailored savings estimates.

Title	Link
Commercial Building Membrane Limited Warranty (Tear-Off Warranty)_Distributors_2021	Download View
GenFlex Lifetime Residential Material Limited Warranty	Download View
GF-Limited Membrane Only-10-20-Yrs-SAMPLE	Download View
Paint Finish Warranty – 35 Yrs – SAMPLE 2008	Download View
Roofing System Limited Warranty – 5-20 years – 100 MPH – CP – SAMPLE 2003	Download View
Roofing System Limited Warranty – 5-20 years – 100 MPH – Hail – CP – SAMPLE 2003	Download View
Roofing System Limited Warranty – 5-20 years – 100 MPH – Hail – SAMPLE 2003	Download View
Roofing System Limited Warranty – 5-20 years – 100 MPH – SAMPLE 2003	Download View
Roofing System Limited Warranty – 5-20 years – 55 MPH – CP – SAMPLE 2003	Download View
Roofing System Limited Warranty – 5-20 years – 55 MPH – Hail – CP – SAMPLE 2003	Download View
Roofing System Limited Warranty – 5-20 years – 55 MPH – Hail – SAMPLE 2003	Download View
Roofing System Limited Warranty – 5-20 years – 55 MPH – SAMPLE 2003	Download View
Roofing System Limited Warranty – 5-20 years – 72 MPH – CP – SAMPLE 2003	Download View
Roofing System Limited Warranty – 5-20 years – 72 MPH – Hail – CP – SAMPLE 2003	Download View
Roofing System Limited Warranty – 5-20 years – 72 MPH – Hail – SAMPLE 2003	Download View
Roofing System Limited Warranty – 5-20 years – 72 MPH – SAMPLE 2003	Download View
Roofing System Limited Warranty – 5-20 years – 80 MPH – CP – SAMPLE 2003	Download View
Roofing System Limited Warranty – 5-20 years – 80 MPH – Hail – CP – SAMPLE 2003	Download View
Roofing System Limited Warranty – 5-20 years – 80 MPH – Hail – SAMPLE 2003	Download View
Roofing System Limited Warranty – 5-20 years – 80 MPH – SAMPLE 2003	Download View
Roofing System Limited Warranty – 5-20 years – 90 MPH – CP – SAMPLE 2003	Download View
Roofing System Limited Warranty – 5-20 years – 90 MPH – Hail – CP – SAMPLE 2003	Download View
Roofing System Limited Warranty – 5-20 years – 90 MPH – Hail – SAMPLE 2003	Download View
Roofing System Limited Warranty – 5-20 years – 90 MPH – SAMPLE 2003	Download View