Shower tray - subfloor prep

[crispy_wafer]

Hi all,

 

What's the general consensus of laying shower trays onto this type of flooring (caberdek), the floor is stable.  However chip goes like weetabix if it gets wet...  Should I cut a section out and replace with ply?

 

[MikeGrahamT21]

I'm also curious to know the best approach to this too, as i have the same job to do this year. Those grey coated chipboards are pretty bomb proof, i used those in the latest extension.

[crispy_wafer]

They do seem it, and It'll be a shame to carve a big hole out of them...

[Canski]

We just laid the trays on to the 22 mm caberdek. ours were quite flat on the bottom so a good layer of sticks like sh*t and siliconed all around the edges. The aqua board will be siliconed at the bottom on to the top of the tray and then the tiles. If that leaks I'll eat my bats.

[Annker]

Caberdek is sound for laying the tray on.

The joints are susceptible to water damage, however looks like they have been jointed with PU glue so that largely negates that risk.

 

 

[Bozza]

When I renovated my parents bathroom last year I replaced the chipboard floor but put ply down where the shower was going,  it was a very heavy stone resin tray and the chipboard was just basic B&Q stuff.  I had tanked the shower area so just tanked the ply area too as had leftover tanking paint.  
 

My plumber nephew advised that they would normally do this (put down ply) but if the floor was sound and new chipboard they would just lay the tray on that, so this corroborates what others have advised.  
 

The top tip he gave me was that to make sure that the floor is proper level if the tray is big and heavy, as mine was.  If slightly out use cement or if just a mil or two out flexible floor tile adhesive down first to feather to a level, then let it dry.  He advised it’s a nightmare trying to level a heavy tray purely with silicone etc as a base adhesive as clearly it will just compress.

 

soz if you knew this, just passing it on if you didn’t.

 

 

 

 

[crispy_wafer]

24 minutes ago, Bozza said:

When I renovated my parents bathroom last year I replaced the chipboard floor but put ply down where the shower was going,  it was a very heavy stone resin tray and the chipboard was just basic B&Q stuff.  I had tanked the shower area so just tanked the ply area too as had leftover tanking paint.  
 

My plumber nephew advised that they would normally do this (put down ply) but if the floor was sound and new chipboard they would just lay the tray on that, so this corroborates what others have advised.  
 

The top tip he gave me was that to make sure that the floor is proper level if the tray is big and heavy, as mine was.  If slightly out use cement or if just a mil or two out flexible floor tile adhesive down first to feather to a level, then let it dry.  He advised it’s a nightmare trying to level a heavy tray purely with silicone etc as a base adhesive as clearly it will just compress.

 

soz if you knew this, just passing it on if you didn’t.

 

No apologies necessary, all good info.  Thankyou. 👍

[MikeSharp01]

1 hour ago, Canski said:

I'll eat my bats

Hmmm I think that may be an offence in the UK.

 

We have just put ours exactly as you have on the Caberdeck glued down and sealed everywhere.

 

 

[Canski]

18 minutes ago, MikeSharp01 said:

Hmmm I think that may be an offence in the UK.

 

I don't care anymore

[Thorfun]

just another perspective here, we cut out the caber deck and fitted shower formers so that the tiles went directly onto the former and everything is level with the rest of the bathroom. we love the sleek look of it. might be something worth considering? unless you specifically want to step up in to a shower that is. 😉 

 

[crispy_wafer]

Shower tray is 35mm, add tiles and adhesive, so there'll be about 20mm +- a bit step.  I don't feel confident with me DIY'ing a former on my 1st floor too much internet reading has frightened the bejesus out of me, so I'm not going to give it any head space.  Yours looks spot on though @Thorfun!

[Thorfun]

4 minutes ago, crispy_wafer said:

Shower tray is 35mm, add tiles and adhesive, so there'll be about 20mm +- a bit step.  I don't feel confident with me DIY'ing a former on my 1st floor too much internet reading has frightened the bejesus out of me, so I'm not going to give it any head space.  Yours looks spot on though @Thorfun!

if you've already bought the tray then it's a no brainer. fitting the former wasn't hard at all. i bought the Impey Aqua-Dec former which was incredibly easy to fit and is cuttable to trim to size. i put 6mm ply on top of the posi-joists and then the former on top of that and screwed it down. then the tiler came along and put 6mm Jackoboard down so everything was level.

[jayc89]

21 minutes ago, Thorfun said:

just another perspective here, we cut out the caber deck and fitted shower formers so that the tiles went directly onto the former and everything is level with the rest of the bathroom. we love the sleek look of it. might be something worth considering? unless you specifically want to step up in to a shower that is. 😉 

 

 

What's the dimensions of that shower area? Looks well!

[Thorfun]

31 minutes ago, jayc89 said:

 

What's the dimensions of that shower area? Looks well!

ended up just a smidge over 1400mm long and 760mm wide after tiles and shower screen.

[crispy_wafer]

I'm just going to drop this here, not only as a reminder to self - as I'll forget, but for others to see in the future.

 

 

[crispy_wafer]

1 hour ago, Thorfun said:

if you've already bought the tray then it's a no brainer. fitting the former wasn't hard at all. i bought the Impey Aqua-Dec former which was incredibly easy to fit and is cuttable to trim to size. i put 6mm ply on top of the posi-joists and then the former on top of that and screwed it down. then the tiler came along and put 6mm Jackoboard down so everything was level.

Spot on, Thankyou.

[crispy_wafer]

Quick question 

bathroom has no wall coverings and studs are bare, should I install the shower tray at this point or install the tile backer boards to floor then drop/slide in the shower tray?