Urgent help needed please

[southside]

I have tiled 600 m porcelin tiles to a bathroom floor on 12mm plyboard which is sound then 100msq screwed.
I have primed floor with mapei prima g
layed the tiles with keriquick flexi layed dry first so the gear didnt go off on me .
left it a day grouted it with jamsine ultra colour
came back over the weekend and there is hairline cracks in the grout between the tiles :yikes: i have never had this before!
i put a verygood thickness of adhesive down i looked at one of the last tiles at the door jam and i noticed a hairline crack between the adhesive and tile itself :yikes:.
and when pressing on it i seen slight movement so i lifted it off to my surprise the wasnt much adhesive on the tile but the adhesive on the wood has even got the code of the back of the tile imprinted on to it .
So theres more than enough adhesive on the ply which is solid and has adhered well to the ply .
Dont get me wrong this was the only tile with a bit movement even at that it was very slight.
But im hopeing the hairline in the grout is down to shrinkage.
I have check all tiles to hear if they are any hollows but there all solid .
surely the tiles are porous enough to stick to adhesive in which btw wasnt to runny or to dry.
All advise will be appreciated
cheers!

 

[Tomtiler]

if the tiles have any dust on the back that might have stoped them sticking with the adhesive

 

[southside]

See what your thinking mate, straight out the box cant see it tbh going to put the one back down then regrout the floor and hopefully everything will be sound ,like i said never had any problems before .
Im just hopeing its down to shrinkage.

 

[david campbell]

can't see it being shrinkage,if it's just the grout maybe it was too wet!

 

[southside]

can't see it being shrinkage,if it's just the grout maybe it was too wet!

Heres hopeing ,[NO SWEARING PLEASE!]nightmare to be honest already been payed for the job too .

 

[hillhead]

maybe adhesive too dry?

 

[david campbell]

did you prime the back of the ply? to be honest it should have really been 15mm ply or bigger,other option would have been cement boards

 

[Rich]

Are you sure nobody came in and stepped on it over night? If the adhesive was just setting off it would have broken the bond and it being right in the door way it would be easy enough to do??

 

[doug boardley]

did you not notice any movement the day after sticking them down (while you were grouting)?

 

[southside]

did you prime the back of the ply? to be honest it should have really been 15mm ply or bigger,other option would have been cement boards

Joiner put the floor down mate seems solid enough i never have had problems with 12mm tbh if the regrouting doesnt work then it will have to get ripped up ,whats confusing i cant see where i have went wrong.

 

[White Room]

Did you back skim the tiles with adhesive

 

[Rich]

Just so you know for the future, david is right it should be 15mm ply min (BS).

 

[Rich]

Did you back skim the tiles with adhesive

Very good point

 

[paulyoung666]

what about the notch size on your trowel , what did you use ?

 

[guil.rocha]

maybe dusty tiles and grout too wet?

 

[southside]

didnt know you had to skim every tile of adhesive before you had to put it down

 

[Rich]

I do on floors and wet areas to make sure you get total bed of adhesive on the back of the tile.

 

[Dontiler]

didnt know you had to skim every tile of adhesive before you had to put it down

yes minimum 80% back of the tile should be covered in adhesive, it gives much better bond, especially porcelain and all natural stone, don't need to spread ceramic tiles

 

[Rich]

I back butter ceramics on floors as well, I dont like any voids under tiles. Ceramic is to soft to risk it with IMO

 

[southside]

I back butter ceramics on floors as well, I dont like any voids under tiles. Ceramic is to soft to risk it with IMO

Well im hopeing i have just put the grout into wet so i will remove it tommorro fingers crossed thats all it is .

 

[Rich]

Let us know how you get on

 

[aqua blue]

Is the cracking all over or just in the centre of floor????????

If the adhesive had not cured fully prior to grouting this may have caused cracking.

 

[southside]

Let us know how you get on

Will do buddy i own my buisness im a plasterer to trade but i obviously do tiling as well and have done for years mainly private ,and some commerical ie starbucks in glasgow and havent had any problems days like these really knocks your confidence.

 

[southside]

Is the cracking all over or just in the centre of floor????????

If the adhesive had not cured fully prior to grouting this may have caused cracking.

All over buddy but on the tile edge not in the middle of the grout im thinking do i take it off now and scrape the floor and tiles while it slighty green and then relay or just scrape out the grout and try that first .

 

[Rich]

I wouldnt worry about it. Thats what is so good about this site, there are thousands of experts on here to give their advice and you cant do anything that hasnt been done a hundered times before. There are far to many guys out there who dont care about the work they leave behind as long as they get paid, at least you willing to find out what happened.

 

[DHTiling]

Cracking on the tile edge is either too wet a grout mix or someone walked on it before grout was dry.
Either way it needs re-doing... as for the loose tile.. sounds like the adhesive skinned or maybe to dry a mix or starting to set in the bucket and no bond was created as the tile was pressed in.

Do a sound test to check for other loose ones.

 

[aqua blue]

Im asking about the centre of the floor area. If there is deflection that's where the majority of the cracking will be. Also have you tried to lift other tiles to check the tile bonding issue further.

 

[southside]

Just seems to be the one at the door jam ,i thinking on the lines of what dave is saying think there a chance the women in the house has maybe jumped in for a quick shower or so .
will scrape it out tommoro apply a dryer mix and see what happens .
Cheers for all your replys guys

 

[aqua blue]

Removing the grout will allow you a better inspection for bonding/movement.

All the best southside.