Stucco metrics: The mighty stucco casing bead

A portland cement-based plaster (stucco) wall cladding system inherently includes its perimeter edges—where the stucco simultaneously begins, ends, and interfaces with other claddings, structural elements, penetrations, and dissimilar materials. How the stucco panel edge condition is designed and constructed critically impacts the function, performance, serviceability, durability, and aesthetics of the stucco cladding as a system, which is not widely recognized or appreciated. The casing bead, as an integral part of the stucco panel edge joint, is the second most misunderstood and misused lathing accessory after the stucco control joint. The need, essential considerations, and requirements for the effective design and installation of stucco casing beads will be presented and discussed.