Cleaning kitchen floor grout lines
I have 12 inch tiles in my kitchen. The grout lines are 1/4 inch wide in a medium gray. After several years, the grout has become a dark gray from embedded dirt. I tried scrubbing some lines with a scrub bruch with Tide and water. It looks better, but this is very labor intensive considering I have about 600 square feet of tile area.
Is there a floor machine I can use for this purpose? It is going to require some type of scrubber. What about a steam type machine? Anyone have success with these? Also if I were to do it by hand, can someone suggest a good cleaning solution or product for this type of cleaning?