Grout that is stained, cracked or falling out can be a serious detriment to the appearance of your tiled surface. Whether it is your floor, countertop, bathroom wall, or tub surround, it looks bad. It can also present problems if water is getting behind your tile. By leaving cracks, you are opening the door for mildew and mold to start growing behind tiled surface.
While it may seem like a complicated problem to fix, re-grouting your tile surface is a job that you can do yourself. With a little patience you will have it looking like a professional job in very short time.
1. Use the Right Type of Grout. The first thing to do is to determine what kind of grout you are going to use. Obviously, if you have a specific color, then you need to make sure you match it up correctly. If you can, break off a loose piece and take it with you to a home improvement store so you can hold it up next the samples. This will ensure that you get a good match.
Typically, if the space between your tiles is larger than 1/8", you'll want to use sanded grout. The sand gives the grout more strength and allows it to hold together better in the larger gaps. If the space is 1/8" or smaller, use an un-sanded grout. The absence of the sand will allow the grout to flow smoothly into the narrower space and you don't need the tensile strength that you would when filling larger gaps. One key thing to remember: Never use sanded grout if you have marble tiles. The sand in the grout will scratch the surface of the marble and it cannot be repaired. Your marble should have been installed with a 1/8" or smaller gap anyway, so this shouldn't be a big issue. But if it is, go ahead and use the un-sanded. The other will ruin your floor.
2. Clean and Remove Existing Grout. Once you have selected the proper type and color of grout, it's time to get down to work. Before you do anything else, make sure the existing grout is clean. Use a commercial grout cleaner to make sure any soap residue, mildew and other everyday grime has been removed, and then allow it to dry thoroughly.
At this point you need to remove all of the damaged, cracked, or crumbling grout. This is done using a grout saw, which you can pick up inexpensively at a home improvement store. Use the saw to break away any loose material. It has a rough carbide cutting surface which actually grinds out the grout more than it cuts it. You must make absolutely certain that there is no loose material left between your tiles. If there is, it will start to fall out later underneath your new grout and all of your hard work will have been for nothing.
Next take a wet rag and dampen the grooves where the grout is going to be applied. Since grout is actually a masonry product and not a glue, some moisture is necessary for proper adhesion. You want to make sure that you don't have puddles, but it is important that the area be damp.
3. Apply Grout to the Spaces. Once you have mixed the grout according to the manufacturer's specifications, you can begin applying it. Use a grout float to spread the mixture evenly over all the of the surfaces that need to be filled. Once they are all full, go back over them with a wet finger to smooth each joint. If you find some low places as you are smoothing the joints, go back over that entire area with the grout float and then smooth it with your finger again.
Once all of the grooves are even and filled, go over the area with a squeegee to remove any excess grout from the face of the tiles. This can also be done with a grout sponge. Try not to wipe over an area to many times, as you may disturb the grout that is drying in the grooves. Don't panic if you do mess it up; just float some more grout over the area and start again.
The manufacturer should provide you with fairly accurate details concerning how long the product needs to dry. Once it has dried, take the time to inspect your work carefully. Grout can shrink while it is drying, and you may notice some grooves that have small gaps at the edges. If this is the case, you need to repeat the application step. Don't be frustrated - it's fairly normal to have to do this twice. When you are shopping you may want to inquire as to whether they carry any non-shrinking grout. It could potentially save you this extra step.
4. Seal the Grout. After you are completely satisfied with the grout work, there is one more step you need to take. The grout needs to be sealed to help protect it against further stains and mildew. The sealer is available at the home improvement store and usually comes already mixed in a handy applicator. Follow the directions and apply it directly to your completely dry grout.
When this has dried sufficiently, take a wet rag or a sponge and wipe any remaining residue off the face of the tiles. This will create a haze on the face of the tile. Allow that haze to dry, and then come back one more time and wipe it off with a dry rag. Underneath you will find your tile looks brand new, with a beautiful grout job to match.
If you are unfamiliar with the materials used in tiling, the grout and the float may seem a little awkward at first. Don't give up though. You'll get the hang of it pretty quickly and then realize that this is definitely a job that you can do yourself.
Source: www.DoItYourself.com
