An expanded market for foamed polystyrene insulation will open up if an industry group gets its way.
The Washington-based Foamed Polystyrene Alliance, a business unit of the Society of the Plastics Industry Inc., is asking building code organizations to approve the use of expanded and extruded PS foam insulation for direct application on steel roof panels.
For years, building codes have dictated that foamed PS insulation be separated from a steel roof by an impermeable barrier — often gypsum. The alliance hopes by removing the need for a barrier, foamed PS insulation will become a less expensive and more attractive option for steel roofing.
``If we're successful, it will give roofers more insulation alternatives and make the market more competitive,'' said Susan Herrenbruk, director of the alliance.
Fire codes do not require barriers with thermoset foams like polyisocyanurate when applied as insulation directly to steel roofs.
The codes are based on results from a flame-spread test method that uses a small-scale model of a building. But FPSA has argued that tests using larger-scale buildings be used because they more accurately depict the fire performance of PS in actual applications.
The larger-scale tests show the insulating panels meet fire performance standards, said Howard Leibovitz, an FPSA spokesman.
The fire burned through the panels quickly, and the flames then burned directly through the roof, venting dangerous gases, according to Leibovitz. Flames did not spread to other parts of the building through the insulation, he said.
Steel roof insulation rules were born out of a 1950s General Motors Corp. factory blaze that destroyed an entire building when a localized fire spread throughout the plant via mineral fiber insulation.
Using the results of the new, large-scale tests, FPSA has persuaded two of the three U.S. model building code writers —Building Code Officials and Code Administrators International and Southern Building Code Congress International — to accept direct application of foamed PS insulation on steel panels.
FPSA now is working on the last of the big-three U.S. code writers, the International Conference of Building Code Officials (ICBO). FPSA officials and members testified before a committee of ICBO's Evaluation Service on July 10 regarding the tests. ICBO could make a decision on the issue as early as September, Leibovitz said.
``That would be really significant because ICBO is very influential,'' Leibovitz said. ``If this were the fight game you'd have a unified title.''
States and cities often base their local building codes on one of the national models.