The Base Test Method has been shown to be a viable means to predict the capacity of gravity loaded standing seam roof systems. However, for uplift loaded standing seam roof systems, the base test method is still being investigated. Previous tests conducted at Virginia Tech in 1990 and 1991 have led to the belief that scatter is inherent in the results of the base test method for uplift.

It was found in this research that scatter does exist in the base test method for uplift loading. Tests were also conducted to determine if purlin size and span could be eliminated from a manufacturer's testing program. It could not be shown in this research that a relationship exists between the percentage of through-fastened capacity, 'R', and the constrained bending capacity of a purlin.