Good evening all.

My next project involves tiling around a bath with a shower within a 7 year old apartment. When removing the previous tiles and walls i found hardibacker board at the shower end of the bath and double skin plasterboard on metal studs at the other ends.

My initial plan was to use 12mm hardibacker boards throughout because i'm installing large format tiles, however i'm having second thoughts becuase of the lack of thermal properties of this board. Is a thermal backerboard such as Marmox thhe only way forward £££, or would fitting i fit 1 x layer of plasterboard and overlay with hardibacker a better way to go?

Alternative sugestions much welcomed as usual.

Cheers
AJ

Is the metal stud 50mm where it was double boarded...

The metal stud is fixed at 600 centres however I can add extra supports

can anyone help please? i need to order materials in the morning....

why do you need the board to have thermal properties?

I would use 12.5 mm Marmox with taped joints and fixed with screws and Marmox washers.


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Originally Posted by Mike

why do you need the board to have thermal properties?

Because i don't want to loose heat within the room via the walls. These walls back onto brickwork voids inside the building.

a stewart says and you could lag the walls if you're that worried about losing heat

Originally Posted by Stewart

I would use 12.5 mm Marmox with taped joints and fixed with screws and Marmox washers.


Created on iPhone.....

Ok.. i hve gone ahead and fitted 12.5mm Marmox boards to the walls arround the bath and on the recomendation of Marmox, ran a bead of sillicon sealant between the boards before butting up.

What should be done with the joints? Should i use a scrim tape to support the joints or do i need to use a waterproof type tape for sealing the joint?

are you tanking the walls? all the joints and internal corners should be taped, and overlap the tape onto the bath about 6mm

Originally Posted by Mike

are you tanking the walls? all the joints and internal corners should be taped, and overlap the tape onto the bath about 6mm

I wasn't planning on tanking. Do i need to?

Highly advisable if you've got a shower over the bath.

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Originally Posted by Mike

Highly advisable if you've got a shower over the bath.

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I haven't used a tanking kit before so what's needed and how do you apply? Thanks.

The Marmox are waterproof so the joints would only need tanking..

there's different makes of kit available from the big tile shops, bal mapei etc. and theyre usually quite easy to do, if you do a search here or youtube you'll probably find a video on it

Originally Posted by whitebeam

The Marmox are waterproof so the joints would only need tanking..

The Marmox waterproof tape is very exspensive for what it is .... Is their any alternatives out there?

Do i need to tape all the screwfixings also?

Do i use scrim joint tape to reinforce the joints prior to fitting the waterproof tape?

hi action,i know it seems expensive however without the tape your boards are no longer a waterproof installation and pretty pointless buying thenm in the 1st instance

is it just over a bath you are doing? if so you shouldnt need too much tape

you may be able to use an other make but would have no come back if it failed as it is not advised for that product

Originally Posted by kilty55

hi action,i know it seems expensive however without the tape your boards are no longer a waterproof installation and pretty pointless buying thenm in the 1st instance

is it just over a bath you are doing? if so you shouldnt need too much tape

you may be able to use an other make but would have no come back if it failed as it is not advised for that product

Hi Kilty, thanks for your help. Yes its a shower area over the bath so a 10m roll should do it!