This stress will be tensile during temperature decrease, or compressive. during temperature increase. If the compressive stress level exceeds the column buckling resistance of. the restrained length, then lateral buckling (or snaking) will occur.
Dry Time. In most cases, you should allow the grout to dry overnight before using that room as total dry time may take up to 24 hours. If you are thinking about sealing your grout after you have installed it, you need to wait even longer than that so that all of the moisture has had time to be released.
Grout the Tile. Then you want to come back and grout the tile, and then after you grout it, you need to wait 24 to 48 hours before that's cured. Then you come back and seal the grout. You probably want to wait 48 hours before you have any foot traffic on that.