Need to repair plasterboard ceiling in shower recess of bathroom. Damage was caused by rain water coming through roof down exhaust vent. This has been repaired by roof plumbing contractor. I am an electrician. My proposed method of repair, remove exhaust fan and shower light. Cut out a rectangular section of existing ceiling including hemp grouting locking plasterboard onto ceiling joists. Replace with 10mm thick gyprock to same dimensions using gyprock screws into ceiling joists. (pre-cut exhaust fan hole) Allow small gap for applying the fiberglass tape then plaster to seal new gyprock to existing plasterboard. Sand back. Apply another thin layer of plaster, smooth off before applying sealer coat and then finish coat. Replace light and exhaust fan.
Refer photos.
Please advise if the proposed repair method needs changing. Is gyprock a suitable repair medium, is it compatible with plasterboard?
