DIY Related: preping new ply walls for tiling

[cyclonebri1]

As above have done a good bit of work in our bathroom.
I have a wall/ pipe screen, 1mtr x 3mtr recently rebuilt/clad in 12mm wsb ply to tile with big porcellain tiles.

Plywood is quite smooth and waxy although new.

Best advice then please? Wire brush and prime with pva immediately prior to tiling with webber flex addy or what??????????????


(my local dealer is a webber stockist)

[Mike]

pva is a swear word on here and not to be used as a primer for tiling. ply is not an ideal substrate to tile on for many reasons, what type of ply is it? you would be better to screw plasterboard to it, an ideal substrate to tile on

[Billy Hunt]

Yeah,ditto Mike,I would be fixing some kind of backer board like NMP to the ply.

[kilty55]

re clad with backer boards if possible

[paul78]

agree with the overboarding. i would be using weber.set spf (not rapid) blue bag. pick up some ad250 also only bout £5 extra.

NO PVA-NO TUBBED ADDY!

[cyclonebri1]

Ok, listened to and heard but this is the scenario. This is vertical stuff. Plasterboard has been removed from the boxing in simply as it was rough and the plywood could be fixed/glued/screwed more effectively.
The job is done, no going back, no redoing.
I have shiny wbp/explywood to tile onto.

Rough it up and no primer before weber flexible or pva.

I have to ask;

whats the issue with pva and tilers????

All plasterers I know use pva to "stick" skimming to old walls, and then tile over?????????????????????????????????????

[deanotile]

Do what you want m8 ! But stop asking for advice as you do not want to listen

[Billy Hunt]

Cyclone,Can I suggest you ask the question on a plasterers forum on how to prepare a background to fixing tiles?Because us tilers who do it for a living obviously don't know.

[grumpygrouter]

Quite simply PVA "primer" can break down when it comes into contact with water and become "live" again, this means your tiles have a layer of damp wallpaper paste between the adhesive and the substrate and the tiles can fall off. Compound this with the fact you have a water sensitive substrate and you are asking for real trouble. Porcelain tiles are heavy beasts and if one should fall off and onto someone (a child?) it would do a lot of damage.

You will find no one on this forum recommending your course of action. Sorry!!

Ok, listened to and heard but this is the scenario. This is vertical stuff. Plasterboard has been removed from the boxing in simply as it was rough and the plywood could be fixed/glued/screwed more effectively.
The job is done, no going back, no redoing.
I have shiny wbp/explywood to tile onto.

Rough it up and no primer before weber flexible or pva.

I have to ask;

whats the issue with pva and tilers????

All plasterers I know use pva to "stick" skimming to old walls, and then tile over?????????????????????????????????????

[cyclonebri1]

Do what you want m8 ! But stop asking for advice as you do not want to listen

It's not a case of me choosing not to do as advised but I have a ready made scenario to start from.
Please don't tell me to stop asking for advice unless you promise to stop giving non usefull advice, cheers chap.

Can I suggest you read my previous threads before you decide if I'm ignoring advice. From an earlier post I made it very clear the full height walls were to be stripped and re done as per valuable advice on here

Perhaps I didn't make this clear but I'm talking about the low level service cover wall behind the wash basin toilet bidet and rad etc.
The situation here was that there is alot of heavy stuff hanging on the wall, plasterboard was considered not supportive enough hence the use of water resistant 12mm ply.

Also the same issue for the bath panel which was to be exterior grade ply with the same tiles, but obviously as a take off sealed panel, what's the advice? 10mm no more ply or similar, would that be durable enough for a removable panel?

[deanotile]

the best advice you will get is in post 2 nothing has changed. hope all goes well for you m8

[deanotile]

if there is a reason you cannot over board the ply with plasterboard then the only other option is to use an S2 adhesive like Mapei S2 quick or similar IMO.

[cyclonebri1]

Ok, now we are being serious, does not a layer of plasterboard on the ply simply add to the "screwed on weight" supported by the framework?? Surely there must be an effective way of adding grip to plywood.

Ps detaails on pva gratefully accepted and factored in, cheers

Please don't think I'm not taking advice but I'm a retired senior,"chief" mechanical engineer and I can't but ask why?

[Rich]

Hi, I have to agree with the gents above to be honest and I cant understand why you would ever "have" to use ply, a cement backer board would have been a far better choice from scratch and I would strongly recommend using a similar board. As said above, ply is really not a very good substrate to tile onto for many reasons. Have a read through the link below, the post is regarding plywood on floors but is the same for walls


Plywood floors...



As with regards to the PVA as a primer, have a look through this link


read: P.V.A. Versus Primers


If you still decide to tile straight onto the ply, then I would use a 2-part adhesive like Mapei keraquick with latex plus, this is available from tile giant but would still be happier over boarding. Hope this is some help.

[cyclonebri1]

Hi, I have to agree with the gents above to be honest and I cant understand why you would ever "have" to use ply, a cement backer board would have been a far better choice from scratch and I would strongly recommend using a similar board. As said above, ply is really not a very good substrate to tile onto for many reasons. Have a read through the link below, the post is regarding plywood on floors but is the same for walls


Plywood floors...



As with regards to the PVA as a primer, have a look through this link


read: P.V.A. Versus Primers


If you still decide to tile straight onto the ply, then I would use a 2-part adhesive like Mapei keraquick with latex plus, this is available from tile giant but would still be happier over boarding. Hope this is some help.

No it's fine and a good help, but try to explain to any woodworker why you should use plasterboard in favour of ply, (ie, plasterboard adds nothing to the structure but ply does), and you may understand my indesision? and what can be done to rescue the situation, yeah.

You guys give dam good advise, but sometimes it needs to be tempered with a little of bit of DIY leeway, if that makes sense, yes you guys are looking at potential liability, (understandable), me? just a good, safe not litigation proof adequate job

[Rich]

Plasterboard will hold a greater weight and if you read through the link I put up in my last post you will see that ply is very problematic. I am trying to answer all of your questions, if I was looking to make something out of wood I would take your advice, take ours on this. Now that the ply is in place and it is not in a shower area I would recommend buying yourself some keraquick with latex plus, should be fine

[widler]

just a quickie mate,i tiled 3 bathrooms in the same house not so long ago,in quite expensive tiles. the joiner boarded the bathrooms out in ply,saying about the strenth factor ect how he has seen this done sooooooo many times ect (ive only been in the trade 26years,so obviously,i know nowt).
long story short,i reboarded 2 in plasterboard,dident do the last one,the owner wouldent let me,so i tiled them all(in flexi adhisive),the wood one dident take but the plasterboard walls are and always will be fine,as solid as my head. ply is not good to tile on,maybe im just unlucky though

[doug boardley]

No it's fine and a good help, but try to explain to any woodworker why you should use plasterboard in favour of ply, (ie, plasterboard adds nothing to the structure but ply does), and you may understand my indesision? and what can be done to rescue the situation, yeah.

You guys give dam good advise, but sometimes it needs to be tempered with a little of bit of DIY leeway, if that makes sense, yes you guys are looking at potential liability, (understandable), me? just a good, safe not litigation proof adequate job

..but we have to get it right everytime .....reputations and all that.

[cyclonebri1]

Hi, I have to agree with the gents above to be honest and I cant understand why you would ever "have" to use ply, a cement backer board would have been a far better choice from scratch and I would strongly recommend using a similar board. As said above, ply is really not a very good substrate to tile onto for many reasons. Have a read through the link below, the post is regarding plywood on floors but is the same for walls


Plywood floors...



As with regards to the PVA as a primer, have a look through this link


read: P.V.A. Versus Primers


If you still decide to tile straight onto the ply, then I would use a 2-part adhesive like Mapei keraquick with latex plus, this is available from tile giant but would still be happier over boarding. Hope this is some help.

Thanks chap, and to everyone else. The advice has been great, the walls have stripped and patched, (plaster on block from new), the floor which is 1/2 floorboarded/1/2concrete has been over boarded in no more ply fixed per recomendations and tiled. You lot sold me on that stuff some time back and yes it is solid.

The rest of the job being low level and most tiles effectively will have fixing bolts through for sanitary ware and accessories so will have to stick with the ply this time, 2 part flex to be used.

Hadn't heard about the PVA thing, the advice seems critical, but, although I'm not a proffesional plasterer I can plaster to a very acceptable standard, learnt simply by watching pro's. But what I can say that even recently all 3 or 4 have used PVA on plasterd or painted walls prior to reskimming, even knowing walls are to be tiled????. Maybe some thing to bear in mind for you guys?

[kilty55]

cyclone bri,pva is fine for plastering in fact its needed yes

it is not for tiling

pva is needed for plastering,plaster skim can hold tiled weights up to 20 k a sq metre so really only good for ceramics so thats fine

its just not fine to then re apply pva on top of the skim coat before tiling

[Rich]

As above.

PVA is fine for plasterers, a HUGE no no in the tiling game.

[Mike]

As above.
PVA is fine for plasterers, a HUGE no no in the tiling game.

game

[widler]

cyclone bri,pva is fine for plastering in fact its needed yes

it is not for tiling

pva is needed for plastering,plaster skim can hold tiled weights up to 20 k a sq metre so really only good for ceramics so thats fine

its just not fine to then re apply pva on top of the skim coat before tiling

i think on over skimmed walls the weight is reduced a lot,no where near as strong as new plaster or plasterboard skimmed

[widler]

game

if we don't treat it as a game,we don't have fun mike

today im playing 'which of my 2 lads can grout with black groutthe best'

[Mike]

if we don't treat it as a game,we don't have fun mike

today im playing 'which of my 2 lads can grout with black groutthe best'

hope you're supplying gloves for them! i hate black, takes so long to clean, even with the washboy

[cyclonebri1]

Ah becoming clearer all the time.
Without wanting to prolong this thread forever, what about tiling on previously emulsioned walls, ie plaster and skim on block walls that have been painted with emulsion?

Actually I wont wait for the reply, it's obvious with a little thought and I've just realised how easy and dust free it is to remove with a wall paper steamer.