Wind loading on commercial roof edge metals: A full-scale experimental study

Abstract

Roof edge metal systems provide an effective interface between the roof of a building to its walls and are used to secure and protect the edge of the roof membrane. Previous studies show that damage involving roof systems mostly occurs because of their failure at perimeter edges under high winds. This study presents an effort to evaluate wind loads on these edge metal elements by conducting full-scale experiments at the NHERI Wall of Wind (WOW) Experimental Facility (EF) at Florida International University. In addition to full-scale aerodynamic and failure assessment test protocols, the experimental campaign, for the first time to the authors’ knowledge, consisted of investigating the effect of wind-induced vibrations on these dynamically sensitive systems. Pressure measurements were conducted at different layers of the edge metals systems by considering the most common installation practices in the industry. The results showed that these roofing elements experience high suctions due to near-parallel wind flows and are susceptible to significant vibration even at low wind speeds, which is a phenomenon not captured in current static pull testing. Moreover, peak pressure coefficients were also observed to increase with wind speeds due to increased dynamic contributions which may amplify the aerodynamic loads by more than about 25%. Furthermore, utilization of edge metal configurations with a higher degree of flexibility was observed to possibly reduce suction on roofing components and appurtenances.