Find the Quality Mark in Polyiso

A 5110-m2 (55,000-sf) portion of the Schuster Performing Arts Center in Dayton, Ohio, features tan-colored TPO (thermoplastic polyolefin), along with polyisocyanurate roof insulation. A new program is designed to help specifiers select polyiso materials with the best long-term thermal resistance.

A 5110-m2 (55,000-sf) portion of the Schuster Performing Arts Center in Dayton, Ohio, features tan-colored TPO (thermoplastic polyolefin), along with polyisocyanurate roof insulation. A new program is designed to help specifiers select polyiso materials with the best long-term thermal resistance.

When it comes to choosing roof insulation, architects/engineers (A/Es) have myriad options for specifying their building projects. However, with a growing concern and increased emphasis on energy-efficient products and practices, one type of plastic insulation is literally setting a new standard.

The Polyisocyanurate Insulation Manufacturers Association (PIMA) has launched an initiative called Quality Markcm, a voluntary program enabling polyisocyanurate (polyiso) manufacturers to obtain third-party certification for the long-term thermal resistance (LTTR) value of their products. The program’s goal is to recognize the very best in polyiso products, and help A/Es when it comes time to select appropriate roofing insulation.

Polyiso is currently used in low-sloped roofing applications in more than 60 percent of all commercial construction and 20 percent of new residential buildings. The material, a rigid foam insulation originally developed in the late 1970s for military/aerospace use, is now selected as an insulation not only because it is energy-efficient and cost-effective, but also because it combines fire safety and compliance with building codes, and offers a range of compressive strengths.

The material passes American National Standards Institute/Underwriters Laboratories Inc. (ANSI/UL) 1256, Fire Test of Roof Deck Constructions, and FM 4450, Class I Insulated Steel Deck Roofs, fire tests without a thermal barrier. Polyiso, a thermoset material, also stays intact during fire exposure in the ASTM International E 84, Standard Test Method for Surface Burning Characteristics of Building Materials (the ‘Tunnel Test’).

Due to its high R-value, less polyiso is needed, which can result in thinner walls, roofs with shorter fasteners, less change in building dimensions to meet determined values, and cost savings through a reduction in materials and labor. (The higher the R-value, the greater the insulating power. Polyiso providers can offer a fact sheet on R-values.)

An independent study by the Energy Services Provider Group (ESPG) used American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) 90.1-1999, Energy Efficient Design of New Buildings Except Low-Rise Residential Buildings, as a baseline to measure economic/environmental results with additional polyiso thicknesses.1 The report suggests increasing polyiso roof insulation thickness significantly reduces energy costs while still providing a positive financial return on the cost of insulation (however, actual savings can vary).


The polyiso industry has converted to blowing agents with zero ozone depleting properties to reflect compliance with the EPA’s Clean Air Act Amendments.

Recognizing LTTR values

The new Quality Mark program for polyiso products is currently the only industry-wide verification for LTTR values, the most advanced scientifically supported method to describe the long-term R-value of foam insulation products. LTTR-values measure long term energy performance of a permeably faced foam insulation product over 15 years.

The program was designed to be a self-policing benchmark against which all polyiso roof insulations can be measured. The
green star logo designates only those insulation products certified to match or exceed listed LTTR-values. It offers design professionals a way to identify and select quality materials for their construction projects.

“Quality Mark will help level the playing field for determining Rvalues by creating an industry standard managed by independent parties,” says Jeff Gould, senior engineering specialist at FM Global, the commercial/industrial property insurance and risk management firm serving as the program administrator.

The use of LTTR-values is fairly new for the polyiso industry, first introduced at the 2002 National Roofing Contractors Association (NRCA) Convention. The LTTR-value method is based on consensus standards in the United States and Canada. PIMA says it provides a better understanding of the thermal performance of foam. Quality Mark is expected to further clarify for specifiers the polyiso products’ long-term performance.

Any manufacturer of ASTM C 1289, Standard Specification for Faced Rigid Cellular Polyisocyanurate Thermal Insulation Board, Type II, Class 1 and Class 2 permeable-faced polyiso foam insulation (produced with a U.S. Environmental Protection Agency [EPA] – compliant blowing agent) is eligible to participate in the Quality Mark program.4 Approved third-party selectors take random insulation samples and pass them to an accredited testing lab that applies the LTTR-values.

After earning the Quality Mark, each polyiso insulation plant continues to maintain verification through a limited testing program. Participating manufacturers are subject to an unannounced LTTRvalue test to spot-check whether future LTTR-values are consistent with the certified values. Currently, six manufacturers are participating in the Quality Mark program: Atlas Roofing Corp., Firestone Building Products, Hunter Panels, IKO Industries, Johns Manville, and RMAX Inc.

Polyiso manufacturers have been working for many years to implement an initiative that demonstrates to roofing contractors, specifiers, and building owners the long-term energy performance of roof insulation. Interest in this issue is growing, and the increased demand to produce energy-efficient and environmentally responsible insulation products influenced PIMA to form the certification program.

“A commitment to the environment and energy efficiency are important parts of PIMA’s mission,” explains Jared Blum, the association’s president. “The very nature of building insulation helps to reduce the environmental footprint of our nation’s buildings.”

About the Author

Lauren Rosenblum is an associate with the Axiom Communications Group. Her articles have also appeared in The Baltimore Sun. She holds an MA in journalism from New York University.


1 The report is available at as “Polyiso Performs: Significant Energy and Construction Savings.” The Web site also contains more information about the Quality Mark program, polyiso applications, and a calculator for determining the thickness necessary to achieve a desired R-value.