Composites have long been used in architecture projects for columns, cornices, cupolas and other decorative elements. But until recently, large-scale use of composites in structural elements such as cladding, roofing and wall panels was rare. Two formidable challenges stood in the way – limited materials included in the International Building Code (IBC) and the National Fire Protection Association’s (NFPA) 285 test. The composites industry has made headway on both, allowing for exciting projects such as the FRP cladding fabricated by Kreysler & Associates for the 10-story expansion of the San Francisco Museum of Modern Art (SFMOMA) set to re-open in 2016.
Changes to the IBC – the primary building code used in the United States – came about with the support of ACMA’s Architectural Division and Fire Committee, association staff and an outside consultant. They spent more than two-and-a-half years working to include FRP composites, test requirements and regulations in the 26th chapter of the 2009 edition of the IBC under section 2612. It is titled “Fiber Reinforced Polymer” and “Fiberglass Reinforced Polymer.”
The chapter explains to designers, engineers and building code officials when it’s acceptable to use fiberglass. It provides standardized regulations and testing for the industry and decreases the “special approvals” needed in the past. While the change has opened up the use of fiberglass in interior and exterior building construction, it dictates that any material incorporated more than 40 feet above ground be non-combustible or pass the NFPA 285 test. The short list of non-combustible materials includes steel and concrete. So materials such as fiberglass must pass the test.
NFPA 285 is the standard fire test method for evaluation of fire propagation characteristics of exterior non-load-bearing wall assemblies and panels containing combustible components. The test is two-fold, requiring both visual observations made by independent laboratories that conduct the test and temperature data recorded during the test. (A list of nationally-recognized testing laboratory programs can be found on the Occupational Safety and Health Administration’s website.)
Prior to landing the SFMOMA account, Kreysler & Associates had to prove its panels could meet the rigorous requirements of NFPA 285. “If we couldn’t pass the 285 test, we couldn’t take on the museum project,” says Kreysler. “And nobody had ever passed it.”
Last year, the SFMOMA and Kreysler & Associates split the cost of the $100,000 test, performed by an independent laboratory. The panels passed. “Now we can use our FRP panels on high-rise buildings,” says Kreysler. His company subsequently fabricated 700 curved rain screen panels, most 5 ½ feet wide with lengths varying from six to 30 feet.
The SFMOMA expansion and two other architectural exterior projects are featured in the May/June issue of Composites Manufacturing magazine. More information on composites and the International Building Code can be found in a CM Interview with Douglas Evans, the fire protection engineer with the Clark County Building Division in Las Vegas.