Insulation behind Aquapanel and tiles?

[sleptwithatradesman]

Hi,

I'm after a bit of advice on insulating behind aquapanel and moisture resistant plasterboard in a bathroom.

I plan on fitting a bath with over bath shower. 1 of the walls the bath goes against is an internal lathe and plaster stud wall, on the other side is a bedroom.
The other wall is an external stone wall with stud attached and lathe and plaster.

I plan on ripping out the lathe and plaster and fitting aquapanel behind the wet areas and moisture resistant board elsewhere then tiling directly on top.

I decided on the above after reading loads of threads. (Thanks to Richard C. posts!)

I'm now thinking I should fit some insulation. Would 50mm celotex/kingspan be ok?

I know there are regs. for sound proofing between a bathroom and a bedroom so reckon this might be enough for the internal wall. I'm unsure if the external wall needs something else for breathing?

I'll be getting a spark to wire in a nice big extractor as well.

Can anybody recommend anything other than the above?

cheers in advance for any replies

 

[sleptwithatradesman]

Anyone?

I'm probably going to opt for 10mm Marmox tile backer due to the cost.

Still unsure if I should bother with any insulation in the cavity?

 

[tfish]

id definitly wack some ridged board insulation in if your battening the ext wall. The wall will be the coldest in the room and attract moisture which MAY lead to mould or damp.

I would make sure the fan is a good un and personally id go for UFH to ensure the floor heats up at least twice a day to dry the room out totally.