Lime/ Lath & Plaster
A very traditional method usually required for heritage work in listed buildings.
For ceilings and timber walls, wooden laths are nailed into place and 2 haired lime backing coats are applied. The 1st coat is applied and marked for a key, then allowed to almost cure before the 2nd coat is applied. Once both coats have sufficiently cured a fine lime putty without the horse hair is added and finished.
Stone and brick walls use the same method, but with the lime plaster being applied directly to the dampened surface. Any deep areas or joints are first filled and allowed to cure, then the 2 haired coats and final finishing coats applied when ready.
All the lime plaster work has to be sprayed with a fine water mist at all stages to allow the lime to cure properly rather than just drying out, which would result in a much weaker surface. This means a much slower finishing time compared to modern techniques.