Is stucco suited for use in a coastal environment?
Portland cement plaster is suited to virtually every type of climate, whether wet or dry and hot or cold. It is popular in coastal environments because it is unaffected by moisture, but when metal lath is part of the system, there are potential concerns due to the elevated chloride levels in the environment. In coastal areas, air is literally salty: it carries chlorides. This is an aggressive ion that corrodes metal. Hardened plaster is not affected by chlorides. If the plaster is direct-applied to concrete or masonry backup, there is little or no metal reinforcement in the plaster. If a 3-coat system is installed, whether the backup is frame construction or to achieve mechanical bond over a solid substrate, metal lath is attached to structural supports to hold the plaster to the wall. The lath is required to be galvanized, and embedding it in a highly alkaline environment like portland cement plaster provides added protection from corrosion. The lath should be fully embedded by the fi
