What plasterboard to use in bathroom

[incubus]

We have a en-suite with a tile shower cubicle on a shower tray. Last week I noticed a damp patch on the ceiling downstairs directly under the shower so I had a look at the grout on the lower tiles and it seems to be leaking. I pulled the tiles off and the plasterboard behind the tiles was soaking and mouldy. I ended up ripping the whole shower and walls out as they were pretty wet.

I wil probably get someone in to fit a new shower/wet room but want to do as much of the easy stuff as possible to keep costs down.

My first question is in relation to the plasterboard to use. I plan on either having the shower area either completely encased in tiles or shower wall panels . My sons bedroom is adjacent to the shower room and you can hear the shower in there when it is running so I also want to have the noise reduced. I was looking around and there are three possible choices:
- Soundbloc gyproc
- Moisture resistant gyproc
- Hardiebacker board.
The sound bloc stuff does say it has some moisture resistant properties but its main purpose is to reduce noise (not sure how effective it will be though as I don't plan on installing the other fancy stuff to reduce noise such as metal studs between plaster and batten) The moisture resistant stuff seems to cover my use and the hardie board says it is moisture resistant and specifically for tiled areas to support the weight. What type of board should I use if the entire area will be covered in either tiles or shower wall?

The second question is to do with the wall insulation. There was rock wool there already but it got wet and was really damp smelling so I removed it. I was going to replace it with earth wool as my local B&Q has it on offer but someone at work told me I should use some of the solid insulation slabs such as kingspan as it will help with noise but I always thought that stuff was for external wall insulation. Any advice on this?

Regards,

John.

 

[roy c]

Use hardibacker board in the shower and kingspan will be ok ...

 

[incubus]

Does the kingspan provide any additional noise blocking over the earth wool? Its more expensive to buy but I wouldn't use it if there isn't additional benefit. Same with the hardiebacker board; its substantially more expensive than the others. If there is not going to be large heavy tiles on it what is the benefit of using it?

Thanks for any advice.
John

 

[peterb20]

Kingspan is approx 3x as efficient as Rockwool for thermal insulation - so 100mm works as well as 300mm of rockwool. Acoustically it is no better - in fact in my opinion rockwool is better because it packs in better, and also the way it is made up is, from a physics point of view, much more adept at stopping sound (its made in layers with alot a air gaps in which stops the sound waves traversing). I would use rockwool for what you need.

Plasterboard wise, its your call. A properly tiled room wouldnt have any issues on normal or moisture resistant boarding. Water wouldnt get through and so it doesnt matter whats behind it. Its true the moisture resistant boarding does give a level of protection, but then if its getting soaked it will fail just as the normal plasterboard would, just maybe not as quickly.

Just my opinion but i think the hardybacker is a complete nonsense. it may well hold heavy tiles much better - but then a properly screwed up piece of plasterboard will take a huge amount of weight (have you ever tried pulling one off???) I know kitchen fitters that fit full runs of wall units on butterfly fixings which are basically hanging off the plasterboard, and they have had no problems.

 

[joe-90]

You should put aquapanel at least in the lower area of the shower - where it always goes soggy. Never seen it get soggy further up.

 

[incubus]

I had thought about using shower wall panel rather than tiles in the shower area. This should reduce the chance of water escape through grout etc. In this instance I would assume there would be no need for hardiebacker or aquapanel board and the standard or moisture resistant board would be ok.

I've pulled the walls down and there was green board in the shower area (tiled floor to ceiling) and the rest of the bathroom was standard board with tiles half way up. It was put in in 1995 and has lasted well so I guess there is no doubt about the strength of the board with the tiles on it. From reading around some people even suggest just tanking the normal board. So many different ways to achieve the same result. I'll wait and see if the missus is wanting tiles or panel and take it from there.

Thanks for the input