Illustrated Architecture Dictionary
Left: Sawn laths .............. Right: Accordion laths
Lath is the basic material used in the formerly common building technique known as lath and plaster, which was used to make interior walls.
One of the key elements of lath, whether wooden slats or wire mesh, are the openings or gaps that allow plaster or stucco to ooze behind and form a stronger bond to the lath itself.
Lath may also refer to wire mesh, typically with a paper backing, that is applied to a wood or metal framework as matrix over which stucco is applied.
Wood laths are sawn roughly 1 1/2" wide by 1/4” thick and 3-4 feet long made form what ever wood was available locally.
In early New England accordion lath was used: 3/8” boards were applied to the framing and split with a hand axe and stretched opening up keyways in the board to hang the plaster on.
- Preservation Plastering, Ltd. (Jan 2011)
Accordion lath is achieved by taking a thin board, randomiy peppering it with hatchet splits, and pulling it apart just enough to crate the gaps into which the plaster may set.
Sawn lath began to appear after 1830 and rapidly superceded accordion lath in every day use.
Since 1950, drywall panelling has made the lath-and-plaster technique obsolete.
- Thomas F. McIlwraith, Looking For Old Ontario, p. 81 (Jan 2011)
Examples from Buffalo architecture: