Once you have installed your ceramic tile, it is time to grout the entire surface. This process is relatively simple, and once completed you can be sure that your substrate and floor is as protected as it can be.
Like many procedures and materials used today, grout originated in ancient Roman times. Marble masons cutting limestone statues and sculptures left a residue of limestone powder on their open-spaced stone floors. When this powder was mixed with sand, clay, and water, the result was a resilient seal between the ground below and the tile. These principles are still in practice today, with what is now known as common grout.
Grout today is a more complex mix of sand or epoxy, hardening agents, sealant, and dyes than what the ancient Romans were inclined to use. Today's modern materials are so simple to work with that in most cases, water is the only additional material to be added prior to application. Please make note of your specific product's requirements, or refer to your local home improvement store professional for any additional information about application or dry times.
Step 1 - Allow Tile Glue Time to Dry
Be sure the tile adhesive has had ample time to dry before you begin grouting to avoid problems. Uncured adhesive can ooze up through the joints and discolor the grout. There is also a potential risk of loosening the bond by shifting tiles. Leave as much time between laying tiles and grouting as possible. Two days is a good time frame, but some floor surfaces may require up to four.
Step 2 - Mix Grout Compound
When mixing your grout compound, it’s important to take into consideration timing since grout will harden in the mix bucket. Start making your mixture, keeping your wet and dry mixture separate to start. Put all of your dry compounds in your mixing bucket, and wet agents in another appropriate receptacle. For non-sanded grout, gradually mix the two together until you get a substance strong enough to sustain a trowel upright. For sanded grout, look for a mixture about the consistency of cookie dough.
When selecting grout, style is not the only factor when choosing between sanded and non-sanded. For joints over 1/8 of an inch, sanded grout is typically recommended, and for all joints smaller than 1/8 of an inch, non-sanded grout is suggested. If your joint is very wide, over 3/8-inch, heavily sanded grout is suggested. Again, refer to your local home improvement store professional or tile provider for their opinion of your specific application.
Step 3 - Prep Absorbent Tiles
Before beginning the installation of any grout, it is imperative that you examine the tile for absorbance. Colored grouts can stain unglazed, absorbent tiles. If this is the case, you can protect the tile using paraffin wax or other protective sealers. If you have any doubts, test a few tiles before grouting the final project. Wet any absorbent tile before grouting to prevent the water in the grout from seeping into the tile, and consequently causing uneven curing.
Step 4 - Apply a Grout Release Coating
This release coating helps in the process of removing excess grout and film in the cleaning stage. This is definitely suggested for unglazed tiles. Use a sponge applicator or mop to apply one of the readily available release agents, full strength, to the surface of the tile. Work carefully and do not allow the liquid to ooze between joints of tile, or it may interfere with the grout. Allow the proper amount of time, as specified by your product, to dry prior to beginning the grouting process.
Step 5 - Apply the Grout
Once the tile is ready to have the grout applied, it's time to get to work. Before grouting, make sure the joints between tiles are clean and free of any debris. Apply the grout with a rubber float trowel, forcing it into the joints and filling them completely; then remove excess grout with the float.
Begin cleaning the tile surface immediately to prevent film or excessive clean up later. Sprinkle dry grout directly from the package over your work area. Then, use terry-cloth rags to rub dry grout into the joints in a circular motion, until the joints are uniform and the tiles are clean. To finish the joint, add a second, very light sprinkling of grout over the same area, and polish it in the same way. Applying grout in this manner leads to harder joints, removes excess water, and fills the joints completely so they are flush with the surface of the tile.
Step 6 - Control Temperature Conditions
Be sure to control the conditions at your work area. If some areas of the floor are exposed to heat, ventilation, drafts, or air conditioning in different amounts, they will cure differently and unevenly. Cooler temperatures cause grout to dry slower and darker, while warmer temperatures result in faster curing and lighter shades. Therefore, it is important to maintain an even temperature and ventilation while the grout is curing for a uniform look.
Step 7 - Remove Grout Film
A finished tile floor will sometimes contain a certain amount of dusting or film. If a grout film develops, wipe the tile with a dampened sponge, rinsing and wringing it often. Re-polish the floor with a terry cloth rag. Avoid acid or bleach when cleaning the floor, as this can discolor the grout and damage the tile.
Step 8 - Damp Curing
Another process associated with grouting is a procedure known as damp curing, and it is recommended to improve the strength of the grout. This is done by covering the finished floor with non-staining craft-type paper for three days. Another method is to wipe the joints with a damp sponge or mop daily, after the first 24 hours, for the next three days.
Step 9 - Clean Up
While clean up may be a project in and of itself, it is imperative to ensure that every excess drop of grout is removed in a timely manner and that the joints are clean in such a way that all are uniform.
Many homeowners decide to seal the surface of the tile once the grout has dried. This simple procedure can be done in a few minutes by applying a solution via a spray bottle and gently buffing the entire area.
Now that you have completed grouting your tile floor, it is time to step back and enjoy it. By now your hard work and effort should be apparent in the finished product.
Sean O'Halloran worked for several years as a Tile and General Contractor throughout the tri-state area. After retiring from the industry, he now focuses on his professional writing career.