Never, let me tell you, never buy a house with 2 cm. wide white grout! Unless, of course, you are going to rip that tile and grout out the day after you buy the house. Grout is man’s worst invention (after war and bombs and all that).
Since I did not know the above rule (not to buy a house with fat grout) I have had to experiment with many a grout cleaner, and the simplest, cheapest, most non-toxic way to clean grout is with two very basic ingredients that I know you have in your house right now: baking soda and vinegar. Here’s how to do it…
First, select a section of your floor to clean for the day. Trust me, you do not want to try to do your entire kitchen floor in one day. This job requires a good bit of scrubbing on your hands and knees. You could probably do an entire bathroom floor if you have a small bathroom. Anyway, select a few short rows of tile. Then turn on some loud happy music and think good thoughts. Take your baking soda and spread some over the grout. Don’t dump a huge heap on all the grout. Just pour a few small piles and use your fingers to spread the baking soda over the grout. You don’t need very much, just as long as there is a little bit of baking soda touching all the grout.
Next you will need a spray bottle. Now you could just fill the spray bottle with white vinegar and use that. I make my own all-purpose cleaner (a mixture of vinegar, lemon juice, dish soap, and water) so I used that. The vinegar and lemon juice are both acidic and act with the baking soda to create the foamy, cleansing paste you need.
Spray the vinegar on all your baking-soda-ed grout.
Now you need a good brush. You could use a toothbrush, but I have this brush, which is like an over-sized toothbrush, with very hard bristles. It is great for cleaning grout. You need to scrub every inch of grout with your brush. It takes a bit of muscle, but it is worth it. After you finish scrubbing, use a rag and a bucket of water to wipe away the baking soda and vinegar paste.
Then, you’re done! And your grout looks like new (until you drop that jar of spaghetti sauce)