What is wire brick lath?
Wire brick lath is a plaster base made of woven steel wire mesh with small nodules of fired clay at the crossing points. The mesh is flexible, so it can be shaped to curved, domed or irregular surfaces before plastering. The clay nodules give the plaster extra grip.
It was developed in Germany by Stauss and Ruff of Cottbus, patented in 1889, and is still known there as Ziegeldrahtgewebe or Stauss lath. In the United States it was later sold as Brick Lath. In the Netherlands, where it is called steengaas, it was used for plastered ceilings under timber joists and for curved ceilings. It is still made for restoration work and difficult shapes.
Recognising it
Through a hole in an old plaster ceiling you see a wire grid with small red clay knobs. From the loft you can sometimes see the back: mesh fixed under the joists, with plaster pushed through the openings.
Application
- Do not hang heavy items from the plaster. Fix lights and racks into the joists above, not just into the ceiling.
- Repair small damage locally. Remove loose plaster, dampen the edges and the mesh, and replaster in coats. If the mesh is still firmly fixed, it can stay.
- Take sagging seriously. A ceiling coming away from the joists can fall in one piece. Prop it and get a plasterer to look at it.
- Think about asbestos. In older buildings, plasters and coatings can contain asbestos. Have suspect materials tested before sanding, drilling or demolishing.
- Repair like for like. In listed buildings, repairing with wire brick lath or a comparable base is often preferred over a new plasterboard ceiling. Ribbed expanded metal lath is a common modern alternative.
Common mistake: simply painting over an old plaster ceiling with loose areas. The plaster keeps working loose and can later come down in large pieces.
Related terms
- Plaster base
- Ribbed expanded metal
- Plaster coat
- Plasterboard
- Clay plaster
- Asbestos
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