Terms of the Trade: What Is a Lath?

The word "lath" has been recorded since the 13th century to mean a thin strip of wood under roof shingles or on walls to hold in plaster and/or lattice work. It has since expanded to mean any type of backing support, including wire mesh, for plaster. What makes lath so effective is that wet stucco or plaster is allowed to settle between the openings created by a series of laths and form a strong bond between the wood support system and the shingles or lattice.