Cavity walls designed and specified for the commercial market in the last 43+ years of my experience in the architectural profession are one of the most misunderstood areas of the design profession. In particular, flashing and weeps are the least understood component by engineers and architects alike in that they feel that these systems are so minor to the entire project that no time is really spent on them.

This article takes a historical journey of the building design concept’s application in the commercial market from the 1930s to today.