Don’t replace grout on a tile floor without cleaning lest you should get the wrong color.
Using proper matting at entrances can dramatically reduce the amount of soil that winds up in the grout lines of a tile floor.
Keeping a tile floor swept on a daily basis will go a long way toward keeping grout lines clean.
Grout lines can be sealed. Water-based sealer is removed every time you clean. A solvent-based sealer can last three to five years.
Brand new tile often needs to be professionally cleaned to remove the grout haze on the surface of the tile. Grout haze is a residue left over from grout being cleaned off the tile.This haze will attract soil and keep the tile from being mopped clean.