Tile grout blown, tiles easily lifted up. what's the problem?

[One Day]

To answer your original question though, how to rectify it. It all needs taking up. Replace the ply with something stronger that's not 6mm ply. if you've damp issues, I'd suggest overboard the floor with 10mm wedi board. Or ditra membrane.
And most important, get a tiler in who knows how to prepare properly!

 

[Brendan1]

Thank you!
So, 6mm is too thin?
if so, what material and mm width do you recommend? I heard backer board is the best.

 

[Brendan1]

is wedi board the same as backer board?

 

[Brendan1]

another issue is that the tiles slope downwards as they approach the front door!
how would i straighten this? is screed the correct material?
Thank you!

 

[Bond]

Many thanks for your replies.

You could be correct about the possibility of damp. We are having to install a damp course into the adjacent walls in the front hallway. Dampness runs half way up the walls.

Saying that, the joists and noggins weren’t damp when the tiles were installed.

Plus, the builder used cheap plywood. Some of it (6mm) went onto floor boards. The remainder was 18mm ply where they were no floorboards.

Is it just damp that would cause the adhesive not to bond to the tile or ply?

Some recommend I don’t use plywood. Do you agree?

What does SBR bonding do (in layman’s simple terms!)?

SBR, is a primer and admixture , which increases bond strength and flexibility.

 

[Bond]

another issue is that the tiles slope downwards as they approach the front door!
how would i straighten this? is screed the correct material?
Thank you!

If you are lifting and replacing the flooring, you can level the floor by fixing timber fillets onto the joists. ( tapering timber pieces, to bring floor to level ,before re-laying flooring).

You say that you have damp , half way up walls. Also worth checking the condition of the over site, (is it sealed). What is the sub floor ventilation like?. Do you have issues of sub-floor condensation. Closely inspect joist ends where close to damp external walls.

 

[Time's Ran Out]

But all these issues should have been addressed by your tiler on inspection before he attempted to lay tiles.

 

[Flintstone]

Your best bet is to get a genuinely good tiler in who knows what's what to sort it all out for you, pay him well and put it down to experience

 

[ATZ Tiling]

Most self levelling have Gypsum in them, so you will need to check for damp prior as this would likely fail too.