I have cracking plaster virtically around a recessed window running either side. Tried filling it but the crack comes back. Noticed it's all blown from the frame to a few inches out so removed the blown bits and find that the crack is where a virtical damp proof membrane is. I tried filling the crack and replastering the blown bits and it all looked good but a few days later I have a hairline crack again. What am I doing wrong? is there some form of mesh or something I should put over the membrane and fill again? or would a bit of caulk adequately fill the crack and I can paint over it?
