Loose floor tiles on Ditramat - Tile Advice

[Terry Rush]

Newbie poster here, in search of advice. We had an extension built nearly 3 years ago, and a tiled floor with UFH throught the ground floor. I’m happy that both the builder and tiler knew what they were doing, and the overall quality of work is excellent, however we have a few loose floor tiles and if I describe the way they were laid and the layers of flooring they’re on, I’m hoping you kind folks can give me some guidance as to how best to fix them.

The main room (lounge) is approx. 7m x 7m, and half the room is a new extension with a suspended concrete block and beam floor, then the following layers:

Ecotherm/Celotex board (100mm I assume)
UFH pipes on top of Celotex (fixed to 5mm building mesh)
Around 3 inches of screed on top.

After about 2 weeks drying, Ditra Mat 25 was fixed to the screed throughout the ground floor. Not sure what adhesive was used, from looking at photos it might have been a mix of Ceresit CT60 acrylic plaster with SBR Bonding Primer.

This was left for 6 weeks before tiler arrived. Tiler then laid a thin layer of Instarmac UltraTile Floor Leveller on top of the Ditra Mat, and then tiled onto that using UltraTile Proflex SP adhesive. The tiles are 40x40cm vitrified.

The loose tiles are mainly around the edges, there are probably a dozen or so that sound loose (hollow), but out of the 80+ sqM of tiles that we had laid that’s a pretty good number I’d say. Problem is several are in areas of foot traffic near doors, and they are now clicking as we walk on them, so I assume it will only get worse unless we do something.

I tried a “Shalex Stickit Tile Repair Kit” from Amazon, which squirts thin glue into tiny holes drilled into the grout, but the whole bottle went down around one tile and didn’t make a difference.

I have now bought some tubes of Fix-A-Floor Repair Adhesive (Fix-a-Floor | Home - http://www.fixafloor.co.uk/) but before I try squirting this into the grout gaps, I thought I’d ask for advice. What I don’t know, is which of the above layers are more likely to have come apart. Is the failure more likely to be between:

Tile/Tile adhesive
Tile adhesive/levelling compound
Levelling compound/Ditra mat
Ditra mat/adhesive to screed

There’s obviously no point in me squirting glue where it’s less likely to be needed, so all suggestions welcome. Or should these tiles be fully lifted and reseated? In which case, any volunteers?

 

[Old Mod]

Hi and welcome to the forum.

Errrrm.... Ditra was stuck down with decorative plaster?
Are it sure it was CT60?
They have adhesives for installing eps boards, but that isn’t CT60.
Typically Ditra will be adhered using either tile adhesive or an acrylic type, such as Ardex AF200.

If the tiles are clicking underfoot, it would suggest they’ve debonded from the Ditra, however, the only true way to tell is by removing tiles in an area that is effected but will not be obtrusive, until it can be remedied.
Also, Schluter do not advocate the use of levelling compound, over their products.
Can I safely assume there are no expansion joints anywhere?
You mentioned problem areas being through doorways, as a bare minimum with a heated floor, there should be expansion joints trough them. No two rooms or hallways are the same temp, necessitating the need for expansion joints through doorways.

 

[Terry Rush]

Forget the CT60, I took hundreds of photos at the time, saw a tub of CT60 in a few photos and jumped to the wrong conclusion. There was all sorts of other work going on. I’ve since seen photos of bags of tile adhesive so I think we can safely assume they used the right stuff to fix the Ditra.

 

[Old Mod]

Well with that argument not withstanding, the rest still applies.

 

[Flintstone]

Was there any expansion gap left to the skirting or wall ? Door frame ? Or were they cut tight?

I’m afraid these wonder cures won’t work for you.

 

[Time's Ran Out]

Can you confirm it was Ditra used and not something similar ie ‘hoover’ as a make not the appliance type.

 

[On one]

So,why was the Ditra fitted after 2 weeks?
And left for a further 6 weeks before the tiler arrived?
Was the person to fit the Ditra not a tiler?
And where does the commissioning of the UFH come in the timescale?

 

[GoneGuy]

Was the ufh commissioned before sutra was fitted?
As there was a big time gap between the Dj tea and tiler was the floor kept clean and dry.
Maybe the tiler dot and dabbed the edge tiles

 

[Old Mod]

Was the ufh commissioned before sutra was fitted?
As there was a big time gap between the Dj tea and tiler was the floor kept clean and dry.
Maybe the tiler dot and dabbed the edge tiles

You wanna lay off the pop Adey haha

 

[GoneGuy]

You wanna lay off the pop Adey haha

Oh dear, well it makes sense to me

 

[Old Mod]

Get there in the end did you Paul @pdc

 

[WetSaw]

Get there in the end did you Paul @pdc

Stoopid little buttons after a night out is never a good combination..

 

[Andy Allen]

Why put self leveller over the decoupler..?

 

[Flintstone]

Tel, where art thou ?

 

[Terry Rush]

Genuine Ditra mat, see photo. Builder refused to use anything cheaper when I fainted at the cost. Photo also shows location of loose tiles. I'm not convinced re expansion joints, the tiler said he had tiled far larger areas than this (on UFH) without. Plus, tiles in the main hallway, kitchen and doorways are fine. Its just round the rear edge near the patio doors that they are hollow and clicky in places. Expansion gaps were left at all edges, then a tiled skirting strip above with silicone beading between, final photo also attached.