Replace or reinstall any remaining damaged or lifted slate and let the floor dry overnight before grouting.
How to grout slate floor tiles.
Then start to apply the grout into the lines and joints in between the tiles by pressing it downwards.
First move the grout float a specially designed smoothing tool that features a flat and mostly firm rubber pad.
2 spread the grout over a small joint.
A tip for you.
Use a grout float to press the grout into the space between tiles.
Begin in the corner farthest from the doorway and work backwards.
It is best to use unsanded grout for slate floors.
Scoop some grout onto the tile floor with a trowel.
Once you have done this only use the other side of the sponge and only once.
By sealing your slate tiles you are blocking the pores of the stone this will then enable the grout to float over the pin head sized holes on the stone not stick within the pores the grout should now be easily removed when it is applied you are now ready for grouting the slate tiles.
Scoop a small amount of grout on a grout squeegee.
Select an area 2 to 3 feet square to begin and apply the grout with a rubber faced trowel to spread the grout across the slates working it into the channels between the tiles.
To avoid spreading the excess grout across your tiles use one side of the sponge to wipe along the joint.
Scrape away any excess grout.