Seismic assessment of rainscreen stucco systems

This paper evaluates the comparative and absolute in-plane seismic performance of rainscreen and nonrainscreen stucco exterior cladding systems for residential wood frame construction in British Columbia. In this study, an experimental program including quasi-static and dynamic tests was implemented, comprised of 18 (in-plane) quasi-static tests and two dynamic tests. The principal parameters investigated in this study were type of strapping, type and length of strapping fastener, and type and length of lath fastener. All rainscreen specimens were constructed with a 20 mm air space. The overall conclusion is that both rainscreen and nonrainscreen stucco comply with the code requirements addressing the permissible drifts. Therefore, both stucco systems were found to improve the structural behaviour when used as the lateral resisting system of residential wood frame buildings. This paper concludes with recommendations for seismic refinements to current construction practices.