plasterboard on stud wall

[mixerman21]

Dear All.
i have made my bathroom bigger with a stud wall and i have bought some moisterproof plasterboard to put in the bathroom does the foilbacked board face me or does it go to the studwall i am thinking the foil faces me in the bathroom so it stops the damp going though the board i will be tiling it when it is up any help please
phil

 

[PrenticeBoyofDerry]

No foil in to wall and paper side facing you, you also want insulate the wall. Is the area your boarding and tiling around the bath or in a shower?

 

[Richard C]

Duplex foil back board is not the ideal choice for a bathroom. The board itself is not moisture resistant & so not really suitable for a bathroom; Moisture Resistant PB is green & would be the best to use.

You also need to consider Building Regulations if there is a habitable room (another bedroom) on the other side of your new stud wall. BR’s require minimum sound insulation standards which must use a suitable density PB with internal sound insulation; there are other do’s & don’ts to consider when tiling “wet areas” as PBD says.

 

[Deluks]

The foil is to stop vapour (steam) from passing through the board from inside the room, and then condensing on the other (cold) side. It will be ok, as long as it's not right next to the bath or shower, otherwise you should think about using aquapanel or similar.
Not related to the question but are you installing an extractor fan?

 

[Chukka63]

is aqua panel the same as mermaid board??.im assuming it is.

 

[Richard C]

The foil is to stop vapour (steam) from passing through the board from inside the room, and then condensing on the other (cold) side.

You set me thinking so I did some checking &, to my surprise, that’s what it says. I’d be curious to know how the hell steam ever passes through the tiling/decoration & the gypsum core to cause interstital condensation on the other side; the core doesn’t seem to be anything special either (moisture resistant), would it not disintegrate eventually much in the same way as standard Wallboard!

I’ve only ever used Duplex under flat roofs & when studding external single skin walls, it’s not something I would have picked for use in a bathroom.

 

[Deluks]

My guess is that as the foil is airtight, then there will be no movement of air from inside to outside, so the steam cannot enter the plasterboard as it would have to force the existing air within the gypsum out of the back.

In a heavily overcondensated room, with no ventilation, I can easily see plasterboard getting damp. Extreme example though, there would be black mould all over the place and no sensible person would be using a room in that state.

Should really be used on all exterior facing walls and ceilings, or walls which have a cold side, such as a hallway wall where a single skin garage is on the other side.

As for it passing through a tiled wall? Possible if the grout can breathe. Anyone who has experienced a roof leak knows that water will enter even the tiniest gaps, water vapour molecules are many times smaller than drops of water so can pass through anywhere really, even your own skin! (Which as we all know is also waterproof)

 

[mixerman21]

No foil in to wall and paper side facing you, you also want insulate the wall. Is the area your boarding and tiling around the bath or in a shower?

thank-u 4 all your replies i have taken the board back and exchanged it 4 HARDIBACKER500 the stud wall is insulated and it has 12.5 mm plasterboard on the bedroomside where the HARDIBACKER is going is in the corner where the bath is going in the bathroom when it is up i am going to tile it do i need to prep it first or straight on with the w/proof tile adevise
thank u again 4 your kind help in the matter

 

[Richard C]

i have taken the board back and exchanged it 4 HARDIBACKER500

Wise move IMO; use 12mm for walls.

the stud wall is insulated and it has 12.5 mm plasterboard on the bedroomside

Ordinary Wallboard won't comply with BR's, it should be a minimum “Wallboard 10” but if your not being inspected then nobody is likely to know about it.

where the HARDIBACKER is going is in the corner where the bath is going in the bathroom when it is up i am going to tile it do i need to prep it first or straight on with the w/proof tile adhesive

Tape the joins & fill with tile adhesive as you tile; primer not generally necessary with Hardi as far as I’m aware, just wipe over with a damp sponge prior to tiling but check the adhesive manufacturer’s instructions. The size/weight of the tiles will dictate what type of adhesive you use; only use quality flexible trade adhesive & grout, not cheap stuff.

Ensure tile joints don’t coincide with any of the board joints.

 

[PrenticeBoyofDerry]

Added info maybe useful link?
http://www.ribaproductselector.com/Docs/7/21107/external/AG044100.pdf?ac=

 

[mixerman21]

Added info maybe useful link?
http://www.ribaproductselector.com/Docs/7/21107/external/AG044100.pdf?ac=[/QUOTE]thanks 4 that the board is 12.5mm did u mean fill in the joints will adsive then tape then addy on top?

 

[mixerman21]

Added info maybe useful link?
http://www.ribaproductselector.com/Docs/7/21107/external/AG044100.pdf?ac=[/QUOTE]thanks 4 that the board is 12.5mm did u mean fill in the joints will adsive then tape then addy on top?

i know this might a silly question one side is slighty rough the other is smooth with writing on it is this the side i tile to?

 

[PrenticeBoyofDerry]

smooth side, facing you.

 

[Richard C]

did u mean fill in the joints will adsive then tape then addy on top?

Fill flush, tape & then skim adhesive over the top forcing it into the tape mesh; don’t put so much onto the surface it causes a bump.

 

[Terry7556]

hi mixerman wise move on the hardibacker, its much stronger than plasterboard in the amount of weight it can support, i think its more thn 35kg per metre square
do you mind saying how much it cost to buy, i want to make a comparison