Help please, tiles cracked/moving - TilersForums.com

[Andy Allen]

I think it's good practice to back butter all tiles

Even mosaics....?

 

[Steve doc]

There has to be more to it than just the tiles not being buttered I think as it looks like every tile has failed ,I haven't seen anything like this since porcelain first come out and some didn't use a flexible adhesive hence the non porous tiles not sticking to the adhesive . I would of thought a decent bal adhesive would of still gripped better than the picture shows.

 

[J Sid]

how much coverage can see ? 100% ? 75% 50% less?, no back butter, and skining over of trowled mix. Whatever suitable adhesive is used it will fail.

 

[Andy Allen]

Imo it's a combination of....

Sticking straight to ply...
Crap adhesive...
To much movement...( Especially with crap adhesive)..
No back buttering, with large format...

Either one or all of the above could of cause this problem....

I would now.....

Strengthen the floor to eliminate excessive movement...
Overboard with Hardie boards glued and screwed...
Tile using a decent flexible adhesive, like bal single part fastflex, or similar...
Back butter the tiles..
Grout with bal wide joint grout with gt1 admixture....or similar...

 

[Steve doc]

how much coverage can see ? 100% ? 75% 50% less?, no back butter, and skining over of trowled mix. Whatever suitable adhesive is used it will fail.

You can see the print of the tile in the adhesive obviously not complete coverage but I would of thought some of the tiles would of bonded it just looks to me as if the bond was broke possible walked on before completely set or adhesive skinned over .

 

[J Sid]

as Andy said, uncouple from the ply. Use a suitable adhesive and fix the tiles the correct way.
before the new ply is fixed, choose an adhesive you plan to use and fix ply as per there that companies instructions. Contact technical dept.

 

[Unused Account 1]

Use ditra on tiles,if bal came out and tileshevent been back buttered ,the blame is off them totally

 

[Balloo]

Here’s a picture of where the tiles have been lifted.

View attachment 106070

From what i can see the ridges from trowel have not even collapsed, its as though the tiler set the tile on the adhesive but didn't push it into the bed,, also the trowel he used looks about an 8mm trowel he should of used 15mm for a better contact,. But most importantly he should never have tiled on plywood as recommended by most adhesive companies.

 

[Andy Rhodes]

Glynn at tilemaster will tell you different Hsp101 flooring plywood (BS 8203:2017-Annex A is more than suitable to tile on

 

[J Sid]

Glynn at tilemaster will tell you different Hsp101 flooring plywood (BS 8203:2017-Annex A is more than suitable to tile on

it may well be if it's fix correctly as per BS
British Standard states
PLY
"The use of sheets and boards that are subject to movement from changes in moisture content should be avoided if at all possible."
"if sheet's and boards are not dimensionally stable with changing humility they should not used in wet or damp conditions."
"Tiles should not bridge joints in boards"
also
the lower face and edges of plywood should be sealed against the ingress of moisture using preferably non-aqueous sealers, e.g. polyurethane varnish, or styrene butadiene rubber, to prevent distortion by changes in atmospheric humidity before being screwed down.