How to fill a tiling gap in an already tiled floor

[amark16]

Hi all
I have a room with a 230x50cm area where a raised concrete base used to be. Kitchen counters used to be on it. This has now been removed and concrete subfloor is exposed. I want to fill this gap with the same type surrounding marble tile. The subfloor is 6cm below the top of the tiles, and the tiles 2cm thick. Attached are 2 photos to help.

1. What prep does the concrete subfloor need before new tiles go in?
2. How do I safely remove the existing partial tiles around the gap without damaging the adjacent tiles, in order to continue with full tiles to the end of the wall?

Thanks!
Tony

 

[Flintstone]

Hello. Difficult to remove the part tiles without damaging the other ones, slowly does it. Tap them with a hammer to loosen them but be carefull when doing any levering. You can bring the level up to where it needs to be on the concrete with self levelling compound

 

[Old Mod]

I’d suggest running an angle grinder a few mil inside the the joint near the last full tile.
The tiles appear to be butt jointed, or very close to.
Trying to separate the cut pieces from the rest will cause damage if you don’t break the bond first.
So running a grinder a few mil on the side of tiles to be removed will achieve this.
Then gently break the remainder away, be sure to move in a direction away from the tiles you want to keep.

 

[Albert]

Hi all
I have a room with a 230x50cm area where a raised concrete base used to be. Kitchen counters used to be on it. This has now been removed and concrete subfloor is exposed. I want to fill this gap with the same type surrounding marble tile. The subfloor is 6cm below the top of the tiles, and the tiles 2cm thick. Attached are 2 photos to help. View attachment 94956 View attachment 94957

1. What prep does the concrete subfloor need before new tiles go in?
2. How do I safely remove the existing partial tiles around the gap without damaging the adjacent tiles, in order to continue with full tiles to the end of the wall?

Thanks!
Tony

The tiles are terrazzo so will have minimal joints and are fixed
with sand and cement, you can as already stated run a grinder down the joint to remove the cut tiles. You can then use levelling compound
to bring the floor up to required height then fix the tiles with adhesive
but to get the same finish as the rest of the floor it will also need to be polished.

 

[amark16]

Thanks for the tips guys, doesn't seem impossible but definitely something to do patiently. No, given that the gap is 6cm deep and the tiles 2cm thick, how much depth should I allow for compound and how much for tile adhesive?

 

[amark16]

So by following your guidance guys, I've managed to remove the partial tiles using an angle grinder and lifting them with a chisel. Now I need to build a base for the new tiles to sit on. After lifting the partial tiles, the existing base is exposed so that should help to build the new base to the existing level.

1. I will build a base out of mortar, my question is, what type of mix to use. I've heard everything from a dry mix such as what they use for shower floors, or a wetter mix (plaster consistency).
2. What's the setting time for the mortar mix?
3. What tile adhesive to use for the mosaic terazzo tiles? Mortar or regular tile adhesive? How much depth to allow for each? Does the mortar need to be grooved?

Thanks!

 

[Flintstone]

I would remove that existing mortar or at least take a good amount off the top. Use self levelling compound, pour it in until it gets to the right level, say 3mm or so below where the tile needs to sit, then stick the tiles down with tile adhesive, the sort in a bag, cement based. If you don’t remove the old mortar your tiles will be proud when you re fit the the new ones