Performance: Qualifying Performance

Metal Roofing Wind Uplift Requirements

Linear Interpolation of Structural Capacity Values Determined by ASTM E 1592-95 Testing

ASTM E 1592 Qualifying Performance

The key distinction in understanding how this new standard applies to your projects is that ASTM E 1592-95 is not a performance standard; it is a standard test method only. The building code, through the calculations described above sets the performance standard. Testing metal roofing systems in accordance with ASTM E 1592-95 provides the assurance that the system can resist the loads required by the code, and that all systems will be compared on an equal basis by using the same test method.

Unlike UL 580, ASTM E 1592-95 tests are taken to ultimate failure. A minimum of two spans must be tested in order to interpolate load data. The following is an example of a system that was tested at 2’-6” and 5’-0”. Ultimate values were 157 psf and 82 psf respectively. The graph shows how these ultimate values are adjusted by a factor of safety, and intermediate span values can be determined by interpolation.

Span	Allowable Load (1.65 F.O.S. rounded)
5’-0”	50 psf
4’-6”	59 psf
4’-0”	68 psf
3’-6”	77 psf
3’-0”	86 psf
2’-6”	95 psf

Last updated: 6/15/00