A building comprises an exterior substrate, such as an exterior prepped for application of a building material and one or more expansion and control joints. A window or door casing has a surface extending above the substrate, and a casing bead control joint with a spacer strip defining a space between the casing and the control joint. For example, the strip is removable by peeling away the strip from an adjacent flange, which may have an optional permanent gasket or back rod preinstalled for filling the space between the casing and the control joint. The control joint may be combined with one or more other expansion or control joints fixed to the exterior of the substrate and a layer of a building material may be applied on the substrate and overlapping a portion of the expansion and control joints.

A metal lath accessory comprising a metal lath attachment feature that includes a side wall, a first flange extending from the side wall, and a second flange extending from the side wall. The first flange comprises at least one barb that projects from the first flange towards the second flange. In some embodiments, the second flange comprises at least one barb that projects from the second flange toward the first flange. The barbs may be configured to engage a piece of metal lath that is inserted between the first flange and the second flange.