Tiling onto 6mm ply

[theskiingbear]

We have just had our bathroom floor tiled onto 6mm ply by a tiler. He was adamant that if the floor shows no signs of movement and the ply is attached every xxx mm (forget the number), that it would be ok to tile as the ply would be teated first with a primer, and flexible adhesives and grouts would be used. Another opinion on this would be appeciated. Thanks

[Dave]

He is wrong... deffo wrong..

[Sir Ramic]

Rather you than me. Minimum overlay for ply would be 15mm but this I would only use if strength was needed. I wonder why he didnt use the 6mm tile backer boards available. ???

[theskiingbear]

I was expecting you to say this and dreading you would. The gout has started to crack, he told us that he didnt have the flexible additive to add to the grout when he did it as it had frozen. Told us no problem as he will rake it out and redo using the additive. We havent paid him but this is the second time in a month we have had the floor done. as the last tiler made a major mess of the floor. Advice herer much appreciated.

[Dave]

Can i ask what substrate you have under the ply..?

[theskiingbear]

Wooden floorboads directly onto joists. The tiler made a real play about the fact that he had fixed these well to the joists and that the ply joints are not over any joist joints. His opinion was that if the floor below the ply is sound and not moving it is Ok to ply 6mm only. He said that 18mm ply would not help if the floorboards are not fixed well. Pushed the 6mm ply on grounds that we would have had a large step between the bathroom floor and the carpeted area outside the door. I am mega stressed that we have got a big issue on our hands, again....

[kilty55]

hi skiing bear,is this the job you posted here a while back? did you prep the room yourself?

[GirlRacerRed]

this is what I found in B&Q today, so I'm not surprised people accept it when a "tiler" says 6mm ply will do the job

[deanotile]

as above 6mm ply is no good and if he wans to argue the toss with you ask him to show you in the British standards (BS 5385) where it says you can use 6mm ply as an over lay. the minimum for ply is 15mm or you can use a 6mm backer board if there is no bounce in the sub floor.

[theskiingbear]

Hi Kilty, its the same job or should i say a redo of the last botch up. No we didnt prep anything, all works been done by tiler. I think given what everyone has said, many thanks to you all, we have to ask them to remove and redo at their cost.

[theskiingbear]

Hi I cant see your quote, sorry, could you tell me what it says in B&Q?

[GirlRacerRed]

Hi I cant see your quote, sorry, could you tell me what it says in B&Q?

B&Q advise that on wooden floors, 6mm ply is sufficient. you are seeing first hand the results of tiling on to 6mm ply. it's disgraceful that B&Q are offering such advice that is clearly inappropriate.

[theskiingbear]

Thanks for the info. I couldnt agree more. Do you agree that we should get the tilers to rip op and redo? They are talking about raking the grout out and redoing with a flexible additive in the grout.....

[GirlRacerRed]

re-doing the grout may be sufficient for a short time, but I bet it won't take long for the tiles to start cracking also.

[kilty55]

Hi Kilty, its the same job or should i say a redo of the last botch up. No we didnt prep anything, all works been done by tiler. I think given what everyone has said, many thanks to you all, we have to ask them to remove and redo at their cost.

hi skiing bear,i asked because i remember your 1st post about bal coming out etc for the bodge job you got, then i read your post looking for a tiler after that 2 weeks ago

it says that the areas have been prepped with ply and aquaboard by the plumbers and are ready to go. that is why i asked did you prep it yourself,but your saying the tiler prepped it.
were the tilers attached to the plumbers /were the plumbers the main contractors? or were they seperate firms paid individually,this is important in regards to who your going to seek to fix it as incase you didnt get anyone from here to do it did the plumbers supply a tiler for you cheers ski

[jay]

any chance of some pics of the floor in question and the problems

[theskiingbear]

Whats happened is we had a contactor in that was due to manage the removal of the bathroom and the refit. They removed and made good the plumbing but they got stuck getting a tiler. Thats when I posted for a tiler, we didnt get any takers unfortunately, shame. We found a tiler, recommended. They came in last week to tile floors and walls but they couldnt as the plumbing wasnt quite right. The plumbing got fixed. The plumbes had laid 18mm ply down but not attached it. As it tuned out the floorboards werent attached well, according to our tiler, so the tiler sorted this and changed the ply to 6mm. The plumbes challenged the tiler on this but the tiler said Ok to go on 6mm ply. I am going to ty and post a pic now.

[theskiingbear]

any chance of some pics of the floor in question and the problems

floor.jpg

Floor laid on the 29th, grouted on the 30th. No traffic on it as yet, bathroom empty... The grout is cracking in one area only at this point, but to me it looks like more cracking is on the way. The minute we start walking on it I dont doubt the issue will get much worse

[jay]

thanks does the floor have bounce in it at the moment say if you walk on it

[theskiingbear]

No, it doesnt seem to.

[jay]

the tile in pic is that the only one that has cracked

[theskiingbear]

Hi Jay, yes it is but as I was saying we havent walked on the floor yet....

[jay]

the cracks in pic are movement cracks not shrinkage cracks 6mm ply is way under specs cant understand why a tiler would downgrade if the right material is already there height diff or not a regrout will not rectify this problem in my opinion and think its best to remove all and re do with the original ply (18mm plus)
cant believe im gona say this but plumber was right
sorry not the news you wanted but best to go over board with prep work than to skimp

jay

[theskiingbear]

Depressing to hear but what I was expecting. Thanks for your view. Someone else suggested backer board, that way we could avoid the step. So we'll pursue this line of discussion with the tiler. I presume the tiles will have to be broken to get them off?

[jay]

if the floor is solid it may need noggin and strengthening and floor boards screwed down then 6mm cement sheeting will do the job but i think the issues you have are in the sub floor good luck and yes tiles if laid correct will be broken on removal talk to the tiler but if he insists on re grout you may want to hold money for a while

[kilty55]

you are risking your job for a 3rd time ski by asking this tiler his opinion on prep work

he clearly doesnt care about prep as he advised 6mm ply,if it was him who done this i would get him to pay another installer to correct it personally

you have already given him the chance to rectify it and his suggestion was to re grout it....thats not the solution

hope you get this sorted it must be a nightmare for you

[deanotile]

in my opinion backer board is the way to go it will not shrink rot or take in moisture and it will not create a step at the door. a quote from BS5385 3.2.4.2
The use of sheets and boards that are subject to movement from changes in moisture content, e.g.
wood-based materials such as plywood, chipboard, wood particle boards, etc. should be avoided if at all
possible. If such boards have to be used they should be restricted to small areas and tiles should not bridge
joints between boards. It is good practice to seal all exposed edges and the backs, but not the faces, of such
boards with a suitable sealer to prevent distortion by atmospheric humidity changes. Care should be taken
to ensure such boards are not installed in a condition where their moisture content is higher than the
ambient equilibrium moisture content once the tiled installation is in use. Failure to observe this can lead
to subsequent warping and distortion of the boards with consequent cracking and delamination of the
tiling.

[theskiingbear]

Its been a total nightmare. Who can you trust??! These tilers have been in business for 20 years and well recommended. I cant believe this to be honest. Thanks to everyone for their comments.

[jay]

you could ask Dave to get someone to have a look if you like its up to you (but its best to let your tiler at least try to fix first) remember you have knowledge now

[theskiingbear]

Cheers!