ANSI/SPRI ES-1 Certification

The turn of the century brought a rash of severe weather events and the promise of a dynamic climate that will continue to produce these natural assaults. Experts around the world agree that we are at the precipice of an extreme weather era. Whether due to global warming or simply following cyclical trends, it seems clear that the frequency and severity of high-velocity wind events will continue to place demands on our structural environment.

Some of the more notorious storms of the decade precipitated intensive study of the vulnerability of roofing systems by organizations such as the Roofing Industry Committee on Weather Issues (RICOWI) and Factory Mutual Global (FM). These studies revealed that the vast majority of all weather-related losses (75%) were due to roof failures, and of those, more than half were due to perimeter failure.

As a result, building codes and standards have evolved to demand better design and performance of roofing systems. The 2003 and subsequent editions of the International Building Code (IBC) contain provisions requiring edge-metal flashings (copings, fascia, gravel stop) to be designed and installed in accordance with ANSI/SPRI ES-1, "Wind Design Standard for Edge Systems Used with Low Slope Roof Systems."

1504.5 Edge securement for low-slope roofs. Low-slope membrane roof system metal edge securement, except gutters, shall be designed and installed for wind loads in accordance with Chapter 16 and tested for resistance in accordance with ANSI/SPRI ES-1, except the basic wind speed shall be determined from Figure 1609.

Although these studies and the adoption of the ES-1 standard by IBC are most directly attributable to the destruction inflicted by hurricanes, events such as straight-line winds and tornadic activity associated with common seasonal storms inflict wide-spread damage each year. FEMA has divided the United States into four zones that reflect the number and strength of extreme windstorms encountered in each region. The tables to the right clearly illustrate that no area is immune to wind-related roofing damage.  

ES-1 Certification Testing Edge Systems from IMETCO have successfully passed the three tests required by the ANSI/SPRI ES-1 standard: RE-1: Roof Edge Termination Test The RE-1 test evaluates the perimeter attachment to a minimum holding power of 100 pounds per foot. The membrane is pulled at a 45-degree angle to the roof deck to simulate a billowing. Failure occurs when the membrane detaches from the edge termination, or the termination detaches from its mounting. RE-2: Pull-off Test for Metal Edge Flashing RE-2 evaluates the strength of the metal edge flashing to ensure that the fascia system meets or exceeds the building's calculated design wind pressure. An incremental load is applied to the face of the specimen and held for 60 seconds, then removed and increased in increments of 25 psf until 150 psf, then increments of 10 psf are applied thereafter. The results must meet or exceed the calculated design pressure of the building. Failure occurs with securement loss of any component of the roof edge, or deformation that would hinder weather protection at the edge. RE-3: Pull-off Test for Metal Wall Coping RE-3 evaluates the strength of a metal coping cap to ensure that it meets or exceeds the building's calculated design wind pressure. Incremental loads are applied as with the RE-2 test, where the load is applied to the face and top simultaneously. Failure occurs with the securement loss of any component of the roof edge system, or deformation that would hinder weather protection at the edge.