I've been staring at the filth I call grout between my tile in our kitchen for months. Mopping, steam mopping, scrubbing, nothing worked. When we were considering selling the house (and since), I thought about getting it professionally cleaned.
Ugh. But I'm cheap. So, I won't.
Then, I ran across some information about washing away build-up out of your hair, a cleansing scrub, and blackhead remover formulas online... all included the household item:
So, I got to thinking... What if I used it on my grout? Its kind of scrubby, cheap... right up my alley.
I mixed about a cup of baking soda with enough water to get the baking soda pastey. One cup won't do more than about 6-8 tiles probably but it keeps me from getting overwhelmed and ultimately wasting the baking soda. Once I had a paste, I spooned it over my grout and commenced to scrubbing with a thin scrub brush. You could use a toothbrush, too, but why do that to your husband?? After you scrub and start to notice the dirt being removed, get a sponge with warm water and simply wipe up the grout. I kept a bucket of water next to me to make it easy.
Its miraculously clean!!! Without professional help. Now, I can't say its a fast remedy. Afterall, I am on my hands and needs scrubbing like crazy. But, hopefully it will be clean enough to seal again and help protect from getting so gross so fast in the future.
Good luck and show me pictures of before and afters!