Replacing a surface FCU with flush

[jonner]

Hello,

I would like to change the surface-mounted FCU for the timed extractor in my bathroom to a flush unit. I have a few questions regarding this:

Firstly, in general, can a plastic dry-lining box be used for mounting a flush FCU, or does a metal mounting box need to be used?

Secondly, since the wall in question is an old lath-and-plaster wall, what's the best mounting box to use in this particular case?

Any ideas would be greatly appreciated, since I'd like to do the same to the shaver socket too!

 

[breezer]

treat wall as plaster board and use dry lining box

 

[jonner]

treat wall as plaster board and use dry lining box

Ok. Do you mean using the box's lugs to force their way into the plaster, or am I getting the wrong end of the stick?

 

[breezer]

dry lining box's lugs go behind platerboard, switch then puuls box to it (if you see what i mean)

 

[jonner]

I see what you mean.

Was reading my diy bible and am now wondering whether the extractor FCU should be in the bathroom at all? Should it be situated outside the room instead?

 

[breezer]

ideally yes, but most extractor fans are ryn from the light cct (no fcu req'd)