Replacing bathroom ceiling (partially)

I am replacing the bathroom in out 1959 era house. its on the first floor under a unconverted loft. Used to be a separate toilet and bathroom, the cinderblock and timber wall has been removed, leaving a interesting state of ceiling as shown in the attached image.

The hallway to toiled ceiling in continuous, less where the timber frames were punched through.

The bathroom has a separate ceiling, that wall was built up slightly higher. The ceiling in the bathroom is in good nick. The one over the old toilet (now going to be a shower). will be replaced. Once complete the shower room will have a high flow inline extractor, and there is a window that opens.


So questions:

1) If I replace just the plasterboard over what will be the shower area, would a good plasterer be able to skim it to join with the existing ceiling?

2) is MR plaster board actually the "best" material for a shower ceiling. I am not a fan of the PVC plastic ceiling cladding but was wondering if a cement board +plaster, wedi board or something else would be longer lasting / better is some other way?

3) in a bathroom ceiling what is the "weak" point - the MR plasterboard, the plaster skim, presumably not the paint. Want to avoid mould growth over the long term.

Thanks!!

After inspecting the to of the ceiling in some detail in the loft I am happy that it's in good condition so I will probably just replace the part over the shower with MR plasterboard

Anyone have any advice to the contrary?

Just fill in the holes with boarding, but you will need battens from above to make sure it's secure.

If you're worrying about damp affecting the plasterboard, then your bathroom is too damp! Fix the ventilation.

Hi ivixor

Thanks a lot for the reply, that's helpful and essentially what I did in the end, after cutting away some parts of damaged old plasterboard!