Optimizing the Wind Uplift Resistance of Mechanically Attached Roof Systems1

Abstract

Wind dynamics on a mechanically attached single-ply roofing assembly can lift the membrane and cause fluttering, introducing stresses at the attachment locations. To identify a component in a system that has the weakest resistance against wind uplift forces, a dynamic evaluation method is beneficial. Over the past 10 years, a number of mechanically attached systems were constructed and exposed to simulated dynamic wind uplift forces using the Dynamic Roofing Facility at the National Research Council of Canada. This paper presents data from this ongoing investigation that will help system designers to maximize wind uplift ratings by choosing the appropriate roof components at the early design stage or by replacing/adding components during reroofing to improve uplift resistance. By diagnosing roof system failures, one can identify the weakest link and select design alternatives that can improve the wind resistance. Through a case study, this paper concludes with a procedure for system optimization.