Plaster is a building finish applied as a workable mixture that hardens, commonly over a supporting base on walls or ceilings.
What this means at your property
After a leak, staining, cracking or separation can involve the finish, its support or both. A painted surface may conceal the extent of wetting. Older assemblies can differ substantially from modern drywall systems.
What should a repair assessment cover?
Ask about the substrate, attachment, moisture condition and materials requiring evaluation before disturbance. The scope should explain whether it covers a local finish repair, replacement of the supporting layers or further investigation of an unstable area.