Industry experience helps with transition

An old proverb advises, "Ask the experienced rather than the learned."

The polyisocyanurate industry has used its experience to convert from hydrochlorofluorocarbon (HCFC-141b) to hydrocarbon blowing agents for the manufacture of polyisocyanurate foam insulation. The polyisocyanurate industry is responding to U.S. Environmental Protection Agency (EPA) regulations that eliminate the production and import of HCFC-141b as of Jan. 1. These regulations are part of the United States' commitment to the Montreal Protocol, an international treaty designed to protect the stratospheric ozone layer. Extruded polystyrene also is affected by these regulations. Extruded polystyrene currently uses HCFC-142b, which is not slated for elimination by EPA until 2010.

This is not the first blowing-agent change for the polyisocyanurate industry, and polyisocyanurate manufacturers' dedication to successfully make this transition is a testament to the industry's ingenuity and commitment to achieving the highest possible environmental performance for its products.

The blowing-agent transition, which took about five years to complete, has been smooth, and product performance will continue to meet industry standards. In fact, members of the Polyisocyanurate Insulation Manufacturers Association (PIMA) have installed more than 1 billion board feet of polyisocyanurate with hydrocarbons as the blowing agent throughout North America during the past three years. These manufacturers report no product performance difference has been observed, and this also is supported by more extensive use of rigid polyurethane with hydrocarbons in Europe during the time period.

A history lesson

The blowing agent is an integral part of polyisocyanurate insulation—it expands the foam and then remains contained in the closed cells, thereby enhancing the foam's thermal performance.

In 1995, EPA announced that HCFC-141b, as a blowing agent, would be phased out during 2002. Polyisocyanurate manufacturers then began the search for a third-generation blowing agent that would meet requirements for product performance and protect the environment. After laboratory evaluation in early 1995, the capability of producing new polyisocyanurate products began. These products were subjected to extensive fire, bar-value and mechanical-performance testing and installed in test roof systems in various U.S. regions.

Along with manufacturers, raw-material suppliers actively were engaged with the polyisocyanurate industry to provide technical support and test programs relating to the R-value of products produced with the new blowing agents. After extensive study, hydrocarbons were selected because they met all products' physical and thermal-performance requirements, as well as environmental considerations. In mid-1998, the first full-time production of polyisocyanurate foam insulation made with hydrocarbons began at Atlas Roofing Corp., Meridian, Miss. The conversion to hydrocarbons is backed by more than seven years of research, development and testing by all PIMA members.

Making changes

During the past several years, PIMA members, NRCA and other industry organizations have worked to incorporate changes into ASTM C1289, "Standard Specification for Faced Rigid Cellular Polyisocyanurate Thermal Insulation Board," the material standard for all faced polyisocyanurate products, including roof insulation. The changes have included compressive strength, dimensional stability and, most recently, the adoption of a mandatory annex requiring testing for long-term thermal resistance for permeably faced products.

Other activities at ASTM International Inc. include introduction of a proposed test method for facer delamination based on the Rolling Load Emulator, which was developed by Firestone Building Products Co., Carmel, Ind.

New industry developments are not always easy to understand. In addition to providing environmental benefits, roofing contractors can expect the blowing agents to perform comparably to products they traditionally use—in all performance factors. PIMA members are committed to customer satisfaction and will continue to work with their customers to answer any questions that may arise about the recent changes, including blowing-agent issues.

Several resources have been added to PIMA's Web site, www.pima.org, to help answer questions about the changes. PIMA's technical staff members also are available to give presentations to architects, roofing contractors and others interested in the issues. Contact PIMA at (703) 684-1136 to set up a presentation or for additional information.

Because the industry currently is adapting to this transition, it would be speculative to say whether it would do this again for another blowing agent—everyone appears pleased with how hydrocarbons perform. At this time, there are no additional EPA mandates for insulation products.

Jared O. Blum is president and chief executive officer of the Polyisocyanurate Insulation Manufacturers Association.