Repairing A Damaged Ceramic Tile Floor
Few finishes can rival the beauty and lasting quality of a ceramic tile floor. A high quality product, professionally installed can, with period maintenance, last indefinitely.
When a ceramic tile floor does need TLC, it is usually because the grout surrounding the individual tiles is stained, cracked or flaking. The grout is the mortar-like material that gives the finished product a monolithic appearance.
Repairing a cracked or chipped piece of ceramic tile is the other most common repair to floor tile. This task is a bit more complicated that dealing with the grout, but can be easily accomplished with the proper tools and materials.
Before attempting a repair, we suggest that you do a bit of investigative work to determine what it is that is causing the damage to occur. This is important because you may complete your tile repair work only to be back in the same boat in short order.
Cracked grout and/or tile are usually the result of a flexing substrate – which’s a technical term for the surface to which the tile is affixed – the floor. Although this condition most often occurs when the floor is constructed of wood with a crawl space or basement below, it can also occur over slab concrete construction.
Over-spanned floor framing, poor or non-existent framing support, thin subfloor material and the lack of a stiffening layer are the most common reasons for cracked tile. One of the most effective means of “stiffening” a floor to prevent it from flexing is to strengthen the floor framing by installing “sistering” floor joist to existing floor joist. Installing blocking perpendicular to and between existing floor joist is another means of accomplishing this.
If the floor framing is solid and the subfloor substantial, the culprit may be a gap between the underpinning “support” posts and the concrete piers. Often, these posts will dry and shrink or the piers will sink creating a gap. This can best be remedied by installing shims into the gap or removing the short posts and replacing them with ones that fit snuggly.
Your best bet to avoid cracked tile on a concrete slab is to divert water surrounding the house AWAY from the house. The soil surrounding the house should be graded away from the foundation. Gutters should be installed to catch rainwater shed by the roof. This water should be transferred by downspouts that discharge the water into a drainage pipe and into a municipal storm drain or other water collection system.
In the case of a concrete slab, cracks in tile are normally result from movement of the slab – expansion and contraction due to changes in the soil condition below the slab. Excess water can cause hydrostatic pressure (water pressure) which pushes upward on the slab from below causing a hairline crack in the tile and/or grout.
Now, with all of these precautions taken, you are ready to repair your cracked tile. The tools you will need are safety goggles, a hammer, cold chisel, electric drill with a carbide tip bit, a grout saw, a putty knife, a grooved trowel, a rubber grout float, a small block of wood, a sponge and some clean white rags. Mastic adhesive, replacement tile and grout are the only materials needed.
The first step in the repair process is to remove the damaged tile. Use a grout saw (a device about the size of a toothbrush) to remove the top layer of grout surrounding the tile being replaced. Next, drill a series of holes using the electric drill and carbide bit. This will make the tile easier to break up without disturbing any surrounding tiles. Use the cold chisel and hammer to remove the tile making sure to wear safety goggles in the process.
Use the cold chisel and a putty knife to completely remove any remaining adhesive to create a smooth surface for the replacement tile.
The new tile is now ready for installation. Using the grooved trowel, apply an even layer of mastic to the back surface of the replacement piece of tile. Set the tile into place being sure that that the joint surrounds the tile is uniform at all sides. Plastic spacers can be used to accomplish this. Using a wood block covered with carpet, gently tap with a hammer to level the replacement piece with the surrounding tiles.
Grout can be purchased in powder form for on-site mixing or premixed. Also, it is available sanded and unsanded. The sanded grout offers greater structure integrity and should be used on joints that are wider than 3/16”.
When mixed, the grout should be of a pasty consistency. Apply the grout with a rubber grout float. For the best results, the grout should be forced into the joints working in a diagonal direction. Also, the float should be held at about a thirty-degree angle from the tile surface. Excess grout should be wiped off using a damp sponge and fresh cool water.
After the grout has dried, a haze will be present on the tile. This haze can be removed by polishing the tile with a piece of cheesecloth or a rag. Allow the grout to cure for a couple of weeks and seal both the tile and grout with a high quality silicone-based tile and grout sealer. This will make the installation more water-resistant and prevent the grout from staining quite as easily.
The biggest challenge you’ll have with this project is finding tile to match. If no matching tile is available, consider removing several pieces of tile at random to create an interesting and unique pattern. Who knows, your repair may turn into a thing of art!