The primary objective of grout repair is to achieve a good bond and color match between the old and new materials. This is often a difficult process, but there are a few tips that may be helpful. Remove as much of the damaged grout as possible using a lightweight hammer and chisel or motorized tool. Thoroughly remove all traces of the damaged grout with a vacuum cleaner or air duster. Clean the existing grout with a heavy duty cleanser to restore its original color, match the new grout, and make the repair.
An effective grout repair depends mainly on achieving a good bond between the old and new materials. This bond typically requires the complete removal of all damaged grout. A lightweight hammer and small, thin chisel are usually sufficient for this task, but a motorized tool may also be used if necessary. Remove the damaged grout until only solid material is left. Avoid hitting the tile during this process to prevent additional damage.
Next, remove all debris from the damaged grout using a broom and dustpan. A vacuum cleaner may be needed to completely clear the area. The bottom and sides of the tile joint must be dust-free to achieve a lasting bond between the materials. It is best to spray the joint with an air duster to remove any powdery residue. A small, clean paint brush may also be used to remove the dust.
A successful grout repair also requires a good color match between the old and new materials. In order to correctly match the colors, the existing grout must often be restored to its original color. A heavy duty grout cleanser may be required for this task. Oxygen bleach may also be needed to remove certain types of food stains on tile countertops and floors. For best results, allow the cleanser to remain on the grout for at least 30 minutes and rinse thoroughly.
To keep the grout repair from being obvious, try to achieve an exact match between the two materials. This may require visiting several different hardware stores to view their color selections. Stores that specialize in tile are usually the best place to find a large selection of colors. Some stores provide color charts or sample pieces of grout that can be brought home for matching. When matching colors, make certain that the old material is completely dry to determine its true color.
Grout is available in different finishes so remember to match the finish as well as the color. If a satisfactory grout color cannot be found, it may be necessary to use caulking instead. Latex caulk is available in many different colors and finishes and is a durable joint material. Before applying the new material, remove any debris leftover from the cleaning process and dust again if necessary.