Plaster / Lathe issue?
Not sure if this is a plaster problem, or a lathe problem, or it might not be a problem at all.....
We have a late 20's brick bungalow with plaster walls. (I'm not entirely sure they are lathed - some of our internal walls had plaster attached to rock lath/gypsum board, but I'm not sure this was used on exterior walls?)
We have a large bow above one of our windows, visible to the eye and only the plaster (the exterior wall structure is sound). The window is still straight and plumb, however the window trim on the wall has pulled away.
It began to happen some time ago, as earlier owners filled the space with caulk or putty of some type . I'm not entirely sure it's getting worse (we've only had the house for 6mo) It's not mushy or soft - the plaster itself seems to be in fine shape. There are no visible cracks in the plaster, only a slight hairline crack in the paint that we applied when we moved in.
Any ideas on what has happened? I suspect the lathe (or whatever was used as a base for the plaster) has pulled away from the brick). Is this something we need to fix posthaste? Should we just keep an eye on it and see if it gets worse?