Whiten Grout
If you are annoyed by dirty floors or dirty wall grout as much as we are, you know that this is one constant battle. It takes hard work, expensive cleaning products that normally don’t work, and lots and lots of perspiration. We think we finally have a worthy solution to this pesky problem.
What you need to do is to spray (liberally) hydrogen peroxide, and let it stay as is for about thirty minutes. After that time, take a grout brush (or any other brush that would fit into those little tunnels), and wipe the dirt off. It should be pretty easy to clean. After that, wipe the grout with some water and let it dry for a few more minutes before you walk over it.