Performance of Cladding in Hurricane Alicia

The performance of building cladding in the Houston-Galveston area during Hurricane Alicia is described. Following an overview of the damage based on the observations made by the writer, various possible mechanisms of cladding damage are discussed. These mechanisms include wind pressure exceeding the design value, missile impact from windborne debris, and performance of glass under dynamic wind loading. Analysis of these mechanisms suggests that impact from windborne debris, e.g., loose sheet metal, roof gravel, broken glass, and parts of the appurtenances from roofs, was the main source of glass damage. In some cases faulty installation practices, e.g., missing jamb blocks, insufficient glass bite, and improper installation, contributed to glass damage. The failure of cladding components other than glass can be attributed to poor connections between cladding components and the main structural system, either by design or by loss of strength in the fastening system as a result of corrosion. Most of the cladding damage from Alicia in the Houston-Galveston area was caused by lack of hurricane-resistant construction, rather than by the severity of the storm. The provision of adequate fastenings and anchorage, and control of the availability of windborne debris, would have substantially reduced the damage caused by Alicia.