Sharing my frustration. Kitchen floor!

[suts89]

Hi,

Have a bit of a dilemma concerning my kitchen floor and would be interested in any comments.


The first picture shows our extension just after completion in early 2011, the floor was fully tiled prior to the kitchen being installed. Rightly or wrongly it was done in this order due to lead time on kitchen and availability of tiler.

The second picture shows the kitchen installed.

To the untrained eye the room still looks the same however I have a number of floor tiles in the space which have become unstable. When I say unstable I haven’t lifted any yet but you can feel and hear movement underfoot.

The extension was built right across the rear of the house and opens up into the original rear sitting room. The floor in the new part is block and beam construction complete with 100mm insulation and 60mm screed. I believe the screed was not perfectly level when applied and the tiler had to apply some self-levelling compound which could be where I'm seeing loose tiles?

The floor in the original part of the house remained untouched and is traditional joists with a 12mm marine ply covering. In here the problem is more apparent and I believe the floor simply has too much spring in it. No expansion joint was placed between the two areas either!

Both floors have a wet UFH system installed.

What I would really like to do is lift all the tiles and re-tile. The biggest issues I can see is
that the whole extension was tiled prior to the kitchen and island being installed on top. Dismantling the kitchen fills me with dread.

The whole space old and new measures 52 square meters.

I guess what I’m asking is “what would you do” ?

 

[Charliesw4]

Hi

I'm a tiler. Few questions...

How big is the screed area and the timber subfloor area?

When you say 12mm marine ply covering joists - do you mean on top of floorboards or directly onto joists?

How long did the screed dry for prior to Tiling?

Is the screed a traditional sand and cement screed or is it a poured gypsum based?

I'll help with a plan if I can

Charlie

 

[suts89]

Charlie thanks for your response it is appreciated.

The screed is a traditional sand and cement and was down at least 6 weeks prior to tiling.

No the ply was directly onto the joists.

The timber floor area is 13m and the screeded area 40m

Thanks again

 

[Charliesw4]

Hi

I'm afraid to say that 12mm ply is inadequate. It should be at least 18mm, preferably 25mm. Who fixed it? They should be replacing the floor.

That part of the floor has failed due to deflection in the ply subfloor and will need taking up.

With regards to the screeded part... The SLC should not cause issues unless it was incorrectly applied or the screed was still too damp. When and how was the UFH commissioned? It must be a gradual rise to temperature (1deg per day). Can you get a loose tile up and take a picture of what's going on underneath?

There must also be an expansion joint where the two substrates meet.

There is no easy fix here, this is a rip up and replace job I'm afraid.

Ditra would be a wise addition to the floor prior to Tiling.

 

[suts89]

Charlie

I am with you and had the kitchen not been fitted on top of the tiles i think i would have already ripped them up by now! Removing the kitchen island and large worktop fills me with dread. I am hoping however that i will only have to remove the plinths on the units against the walls and will then be able to lift the tile enough under the unit. (if that makes sense)

The UFH is a wet system and so is below the 60mm screed. Following the tiling it was not switched on for at least 1 month and then manufactures recommendations were followed.


With regards the Ditra could you give some more details please? What does it do and would you have recommended it throughout?

Thanks again