You can avoid cultivating mould and having the lingering smell of damp by ensuring the bathroom has adequate ventilation.
Install an efficient, fast-working exhaust fan for the best solution.
1. Mark the ceiling position
Access the roof cavity to locate the ceiling joists.
The fan should fit between them.
Use masking tape to position the template supplied with the fan and mark the outline with a pencil.
2. Cut out the ceiling
Drill a 10mm diameter starter hole inside the marked outline and cut using a hacksaw blade or a jigsaw set on slow.
3. Install the fan
Have a qualified electrician hardwire a powerpoint into the ceiling cavity near the fan.
Plug the unit into this before installing.
Fit the unit into the cavity, slowly pushing it into place so that the spring clips lock onto the back of the plasterboard.
Clip on the cover plate and switch on.