Advice please: tiling onto WBP plywood

[k8ngj]

Hi there

Just had a new shower/bath fitted and replaced the area with WBP plywood as it needed to hold the shower unit.

As its a small area I've decided to do the tiling myself. We have been to Topp Tiles to see which tiles (400mm x 25mm) we want and after a bit research is it advisable that I use powder mix adhesive due to the size of the tile rather than the ready mixed stuff?

Would this stuff be ok? http://www.toppstiles.co.uk/tprod2950/section172/Bal-Single-Part-Flexible-Grey-20KG.html

Do I just mix it with water?

Also as the wall I'm tiling onto is WBP plywood, would I need to do anything to the wall/area beforehand?

Thanks in advance!

 

[Richard C]

Should that tile size be 400 x 250mm? I would never, ever advise using WBP ply as a wall tile base & you’re just asking for trouble using it in a wet area unless you tank it; always use waterproof tile backer board. WBP ply is made from wood & wood is not dimensionally stable when exposed to moisture. Waterproof adhesive & grout is only waterproof in the sense it won’t disintegrate when wet, it will still absorb moisture; if moisture gets through to the ply, it will warp & there go your tiles.

If tiles are 400 x 250mm SPF is fine but what thickness/weight are they? I would seriously advise you either change the WBP for a waterproof, 12mm tile backer board or tank it but if you have a recessed shower valve, the back of the ply will still be vulnerable if you get any problems; results on your tiles will be the same.

 

[k8ngj]

Hi Richard

Thanks for your reply.

The reason why we used WBP ply is because it needs strengthning to support the shower unit that we have fitted.

Will waterproof tile backer board be strong enough to hold the unit in place?

 

[Richard C]

You don’t say but, presumably, it’s a stud wall? I understand why you’ve used ply; it’s just not the way I would ever recommend it, let alone in a wet area; there are other ways. What type of shower is it, surface mounted or recessed? Is the pipe work fixed to the surface or behind the wall within the stud?

Was that tile size right at 25mm wide? Topps can have some bargains for tiles but they should come with a "wallet health warning" when it comes to their prices for decent trade adhesive & grout. Always ask for a discount but you might not get one unless you can convince them your trade.

 

[tpt]

agreed on the wallet health warning

whats the tile?

 

[k8ngj]

Can't find the exact tiles but they are similar to these
http://www.toppstiles.co.uk/tprod4757/section1196/Fox-Blanco-25x50cm.html

Its a Aqualisa aquarian shower, other than the shower rail and the temperature control unit everything will be hidden behind the ply on the stud wall.

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[Richard C]

So the tiles are 25cm & not 25mm? It is important; the tiles may appear similar but it’s important you confirm what type they are; ceramic, porcelain or (but unlikely) natural stone?

With pipe work concealed behind the wall you should be using waterproof backer board not ply. As long as the pipe work is well supported within the stud & you introduce a timber noggin or two support the mixer valve behind the backer board then it will be fine .

 

[k8ngj]

Thanks Richard for answering my question, been very helpful.

Will try & source some backing board over the weekend and change the ply

 

[xr4x4]

Isn't WBP ply waterproof?

(Water and boil proof)

I left a puddle on WBP ply overnight, it's was still there in the morning..!

(I make a mess when making tea!)

 

[Richard C]

Isn't WBP ply waterproof?
(Water and boil proof)

Only the adhesive is Water & Boil Proof which prevents the wood plies from de-laminating, the wood itself isn’t waterproof. Wood wlll expand when it gets wet & old clinker construction (look it up) boats used to rely on it to prevent leaks! If your wood tile base gets wet, it will expand & there go your tiles!

I left a puddle on WBP ply overnight, it's was still there in the morning..!

On an untreated WBP surface I don't believe that but it proves ???? hardly any sort of test!

I make a mess when making tea!)

We all do but it’s usually on a wipe clean laminate worktop!