Slightly loose floor tiles

[whoschuffed]

Hi all, recently bought a house that has underfloor heating downstairs. It was installed when the house was renovated probably about 12 months ago.

Cue us buying the house and moving in, i'm noticing with a couple of the floor tiles there is a very very slight tip/wobble when you walk across a couple. It's not a noticeable tip or wobble and the grout looks to be in tact mostly (there are a few areas where it looks to have crumbled away) but i'm wondering what the best way to tackle these tiles would be?

Is it a case of trying to carefully take the tile up and re-seat it?
Or are there some tools/fixes that can be used whilst the tile is in-situ to reinforce it from behind?
Or would simply regrouting where the grout is missing work the best?

 

[opps]

In time the grout will fall out and get sucked up by the vacuum cleaner. If you re-grout, the same will happen but later down the line..

Is the underfloor heating water or electric?

 

[whoschuffed]

The UFH is water.

 

[robinbanks]

If there is a wobble all round the tile should pry up with a bit of jiggling, so you can have a look at the substrate and tell us what it is..

Pics of the upside down tile next to the hole it creates when lifted, please

 

[whoschuffed]

There isn't a wobble all round the tiles in question, its a very very slight tap noise i can hear when you step on them in a specific part (and you can see where the grout has become loose). I'd rather not have to take the full tile up really if at all possible, would there be a solution where I can leave a tile in-place?

 

[freddiemercurystwin]

As mentioned you need to establish if there is a subsrate or similar issue going on or it's just a couple of ill fitted tiles.