wall prep before tiling shower...

wasim21k · Post by **wasim21k** » Tue Jul 18, 2017 11:54 pm

Hi,
I am after some suggestion/advice on preparing wall and wooden floor before tiling.
my initial plan was to just replace floor tiles as most of these were cracked over time and there is always small water leak whenever someone takes shower (now i know why),
It looks like I have opened the can of worm.

I am sure I have to replace plasterboard with cement board (as I read from other posts) but question is do I have to remove all plasterboard or can I getaway with just replacing half (about 5 tiles from shower tray corner on each side of shower tray?
What about floor? Do I need to put poly and tile over it or poly first then cement board on top of it and then tile?

davyp1 · Post by **davyp1** » Wed Jul 19, 2017 8:05 am

Sorry. but I am not clear as to what you mean by 'poly'!

Looking at your floor first, you do not say how it has been prepared previously. By you saying that most tiles are cracked I am assuming that the tiles are stuck down direct to tongue and grooved floor-boards?
If this is the case, you need to remove all floor tiles and adhesive from the T&G floor-boards.
The floor is then covered with 6mm thick ply-board bonded at joints and fixed at 15cm centres either with 1" anular ring nails or 1" screws. This ply is then given one coat of PVA (Diluted per instructions on the can) prior to tiling.

Walls, you need to strip off all tiling and establish what extent of plaster-board requires replacement.
Plaster-board or cement-board is entirely your choice. While cement-board will not disintegrate when damp, neither will plaster-board provided it is not allowed to get wet in the first place.
To help prevent any future leaks, you need to fix a sealing strip between the shower base and the wall/s to which it abuts.
See link: https://www.buyaparcel.com/p/mx-flexi-s ... gJaR_D_BwE
Then complete the wall-tiles finishing the internal shower area corners and junction with the shower base with a good quality silicone sealant.

davyp1

wasim21k · Post by **wasim21k** » Wed Jul 19, 2017 10:51 am

davyp1 thank you for quick reply.

poly was as typo, i was referring to ply-board.
its tongue and grooved floor-boards and hard board screwed on top of it and then tiles. all adhesive with hardboard will come off to lay new ply-board on top of T&G floor.
6mm ply-board alone enough for floor? i mean without any cement board on top of 6mm ply-board?

i wish i can remove shower tray and fix this mess properly but shower tray wouldn't move at all, may be because its fixed with cement to the floor? Any idea how i can remove it?

Only front wall is damaged intensively as you can see in the picture, i m thinking to remove all plasterboard from front wall and half the wall on right side to cover all the shower sides.

davyp1 · Post by **davyp1** » Wed Jul 19, 2017 11:32 am

Hi wasim21k,

Just a couple of points before I answer your questions.
The wires stuck out of the wall? Have you isolated them at the distribution box?
At the very least, they need to be taped up separately with insulation tape while power is off!

Your hard-board has not been fixed at 150mm centres. You need to make sure that the new Ply-board is.

When they fitted your shower tray, they will have removed certain floor boards to accommodate the shower waste pipe.
The trap and the 1st section of waste pipe will have been fitted prior to positioning the base and then the final piping up would have taken place.
You need to carry this out in reverse. First locate & remove the access boards and separate the waste pipe at a joint near to the tray.
I doubt if they will have stuck the tray down, but spare adhesive from the iles could be holding it down.
Take an old wide chisel and hammer and with the chisel flat to the floor & the blade aimed at the joint of floor boards & tray, give it a sharp tap then move on 20cm and repeat till it frees itself.
It went down, so it will come up again.

Ply-board is fine for the floor as long as you fix it as I have said previously. Also you must use a flexible floor adhesive for the floor. And remember, without any leaks your floor should see hardly any water! Just the odd splash. I am assuming that you will be fitting a shower screen not just a curtain?

Another point. Your Toilet should be fitted on top of the finished floor. At the moment it is fixed to the floor boards.
You need to remove it and fit it back on top of the tiles when the floor and wall tiling are complete.

davyp1

Greg Williams · Post by **Greg Williams** » Thu Jul 20, 2017 12:47 pm

The shower tray must be isolated with silicon around the edges from the floor and from the walls. You should cut those silicon fixings to easily remove the tray. Good luck

wasim21k · Post by **wasim21k** » Fri Jul 21, 2017 2:52 pm

hi,
first of all thanks for advise, safety always first, those wires are isolated at distribution box but added safety i have taped them separately with insulation tape now.

i manage to lift shower tray so its not glued to the floor, i think i only have choice to cut floor board to make access or cut ceiling from under side to gain access to waste pipe and trap. on second image those red lines are joist and blue line where waste pipe is and green box where i think is best place to cut the board. shower tray must be installed after putting down these t&g boards but before installing ceiling board on underside

as i don't see any access board. any other suggestion?
on front damaged wall can i put cement boards on top of exiting plaster board or i must remove it and put cement or moisture resistant board? insulated plaster boards.

toilet was fitted on top of tiles and it will be fitted on top of tiles.
thank for help.