To any home owner who has tile floors know dirty grout can be a eye sore. What grout is, is a thin line of mortar, or plaster used in masonry joints. And over time accumulates dirt and dust and other unwanted debris. It can also start to be covered up with soap scum, and other mineral deposits. Mold can also grow in your grout. Cleaning it however is not costly or time consuming.
You can use a commercial cleaner, or plain old vinegar to clean that grout back to looking new. If you want to do it with vinegar, just spray your grout and wait twenty minutes. If you have mold in your grout always use a respirator dust mask and gloves for protection. Just scrub your grout gently with a small brush like a old toothbrush. Rinse your grout well. If it's grout in your shower use your shower head to rinse the grout dirt away. If it's else where use a spray bottle of carbonated water. After you rinse, check for any stains that may be on your grout. Toothpaste (not gel ) placed on your grout stain will scrub it away. Leave it on for twenty minutes as you did the vinegar, scrub, and than rinse away again.