So I tried putting redidrive-type fixings into the sides of the recess. I guess it's plasterboard as it's an early 70's house, but it seems to be more plaster than board, as the fixings have now chewed large holes in it and are rotating freely.
My best guess now is to fill the holes with something that's liquid enough to bond the edges of the plaster too. Then I would redrill for narrower fixing; possibly those butterfly-style plastic ones where the wings pop out on the rear side of the plasterboard. My questions are:
- Is this a good idea?
- What kind of bond / filling stuff should I use, or do I need to bond the plaster edges first then fill the rest?