Not filling the gap can allow water to migrate undeneath the tiles.
Gap between floor and wall tiles.
As the tiles increase in size a larger gap becomes acceptable.
If you have tile on the wall adjoining the tub select a caulk that matches the color of the grout.
Caulking is the best choice for this application.
Never fill this gap with grout because tile grout is not flexible.
It might loosen them and might rot the floor.
Instead fill it with an elastic material capable of sustaining the movement of the floor and the movement of the wall.
These can be left in place and will not be seen when you have completed your tiling.
The gap goes 3 5cm to 4cm back to the breeze block.
Fill gaps larger than 1 8 inch.
The d i y video how to seal a big gap between tile floor and tile wall in a bathroom or shower.
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The large format 18 inch tiles should have inch space in between.
If your gap is smaller than 1 8 inch in width use regular caulk.
Place them between the tiles are you lay each one and grout straight over the top.
For smaller tiles is advisable to use small spacers.
Gap between floor tiles and wall tiles.
Gently push the tiles together so the spacers are tight in the joint.
The tile council of north america recommends at least a quarter inch gap between the tile floor and the walls.
There is a gap of say 5mm to 8mm give or take high between where the floor tiles meet the wall tiles in the bathroom.