Formal Engineering of Residential Buildings

Abstract

The performance of residential buildings during hurricanes is as important as the performance of other buildings. Buildings where people live and where they are likely to be when a hurricane strikes must survive. If this premise is accepted, it follows that residential buildings should be afforded a degree of engineering attention that is commensurate with that given to industrial and commercial buildings. Building code authorities have not been blind to this need. In new procedures adopted for hurricane zones in the United States, common sizes and geometric shapes of timber and masonry residential buildings are formally engineered, and associated construction details are placed into prescriptive codes for use by homebuilders. In this way, these structures can be constructed according to engineering principles but without requiring the formal engineering of individual buildings. While improving the wind resistance of residential buildings to some degree, this change to the homebuilding process is not achieving the desired result. In many instances, homebuilders have retained engineers to certify their designs rather than work with new prescriptive codes whose details vary considerably from traditional construction. For several reasons, these engineers do not design the houses in a formal sense. A review of these new prescriptive codes and their implementation leads to the conclusion that houses which can perform adequately in hurricanes can best be achieved by following design procedures established for other important buildings. This includes the submission of “sealed” drawings that are backed by calculations, and audited through conventional plan-review processes.