Cladding Loads: The Influence of Balconies and Slab-Edge Storm Shutters

One of the consequences of Hurricane Andrew in southern Florida during 1992 is that many condominium buildings in the fifteen to thirty story range are now being designed with balcony- edge storm stutters. These shutters are intended to reduce the devastating damage that strong wind and rain can have when the building envelope is breached. In fact, recent experience in the United States suggests that residential damage claims are 40% larger when the building envelope is breached. The increase in internal pressure after cladding failure can create other cladding breaches on that floor or in that apartment. These events are frequently the cause of massive insurance. With the shutter option the prudent cladding designer is now interested in two physical geometries: (i) the open balcony condition with no storm shutters present and (ii) the building with slab-edge storm shutters installed. The latter effectively changes the shape of the building from a rough-surfaced collection of protruding balconies to a much cleaner, often rectilinear, structure. The purpose of this paper is to demonstrate the significant differences in cladding pressure for the two building configurations.