Which statement best describes metal lath used for plaster and stucco in California?

Which statement best describes metal lath used for plaster and stucco in California?

• A. Expanded metal lath and wire lath are common metal lath types for plaster and stucco
• B. Wood lath is a type of metal lath
• C. Plastic lath is the only metal lath used
• D. Aluminum mesh is never used as lath

Answer: (A)

Metal lath serves as a mechanical key and backing that helps plaster and stucco adhere, dry properly, and resist cracking. In California practice, the two most common forms are expanded metal lath and wire lath. Expanded metal lath is made by slitting and stretching sheet metal to create a rigid, diamond-shaped mesh, which gives a strong base that plaster can grip into and stay in place. Wire lath uses galvanized wires woven or welded into a mesh, providing a flexible surface that still provides a solid key for plaster to bond to and flow through in places to improve interlock. Wood lath is not metal lath, so it doesn’t fit the description. Plastic lath exists but is not the only metal lath, and aluminum mesh is used in some cases but not universally or exclusively. This is why expanded metal lath and wire lath are described as the common metal lath types for plaster and stucco in California.

Metal lath serves as a mechanical key and backing that helps plaster and stucco adhere, dry properly, and resist cracking. In California practice, the two most common forms are expanded metal lath and wire lath. Expanded metal lath is made by slitting and stretching sheet metal to create a rigid, diamond-shaped mesh, which gives a strong base that plaster can grip into and stay in place. Wire lath uses galvanized wires woven or welded into a mesh, providing a flexible surface that still provides a solid key for plaster to bond to and flow through in places to improve interlock. Wood lath is not metal lath, so it doesn’t fit the description. Plastic lath exists but is not the only metal lath, and aluminum mesh is used in some cases but not universally or exclusively. This is why expanded metal lath and wire lath are described as the common metal lath types for plaster and stucco in California.