Yay, plaster repair time! Our plaster walls consist of thin strips of wood lath nailed to wood studs, then a mix of plaster and horse hair was applied, and keyed into the space between lath strips. Here is a close up of some authentic old- school horse hair in plaster… Usually they mix it in more…
Although most of the plaster in our home is in good shape for its age, There are definitely a few areas where the plaster has started to pull away from the lath. Sometimes in un-repairable chunks that will be infilled with drywall mud:
OR it can look like a large lump and feel like a trapped air bubble when you push on it, basically held together with paint and magic horse hair but no longer attached to the wood, and if that’s the case you can usually repair it. Just the thing:
These washers pull the plaster back to the lath, then use drywall mud to cover the washer and sand away to a smoothe finish. We’ve already gone thru 50+ of these guys just on this part of the project!