Best way to clean and seal grout, and should you seal grout when not in a wet area?

Answer 1

Actually a good trick to clean grout is to use toilet bowl cleaner if you have any handy. Be careful not to get any on your stainless steel items like your faucets, tub drains etc. They will corrode. Really the best way is to get a good scouring cleaner like Comet or Ajax and a very stiff bristle brush and go to work. A lot of elbow grease and patience is required.

To answer the other question. The reason you seal your grout is to keep moisture from getting to the underside of the tile. This can be caused just by humidity alone, not necessarily by direct water contact. The other reason to seal is that it will actually help keep the grout clean as dirt will have a harder time penetrating it. It will also make it easier to clean when you have to do it.

Answer 2

I can tell you that Tylex mold and mildew spray works miracles on seriously stained grout.
My experience was when we lived in Germany my husband had butter fingers and dropped several bottles of soy sauce on our kitchen floor just outside the fridge. We had light grey tiles and grouting which was not sealed and I was paniced about when we move that stain my not come out. By chance one day I was cleaning the bathroom and absentmindedly walked out of the bathroom still carrying the bottle in my hand. I thought .. what the heck... I sprayed a small spot, grabbed my scrub brush from under the sink and gave it a little rub and wouldnt you know it the grout came CLEAN! like the soy sauce never existed! I was so happy to discover this I used it on every square inch of grout in the kitchen and I passed the move out inspection with flying colors!!

Good luck.