Tile Grouting for Floors and Walls

Wall and floor tiles sometimes leak grout. We see fixtures that are many years old that have never lost grout, and ones that were done in the last year need attention. Facilities or construction problems combined with settlements are the cause. I recently saw a house built in the 1950s and the tiles looked brand new (in fact, they had gone out of style and made a comeback) and the installation looked as perfect as it did 60 years ago.

Tiles are fixed to the wall or floor (most often) with a thin layer. Thinset is a process that uses a special adhesive to bond tile to a substrate, such as waterproof gypsum board or reinforced backer board. Once hardened, the fresh grout is forced into the spaces between the tiles with a rubber trowel and cleaned. When the grout fails, the danger is water, which finds its way into the thin layer. This starts the process of releasing the tile from the substrate. Water can pool behind the tile and develop mold. This mold will eventually show through the grout and the shower will start to smell like a swamp. We see this every day. This is why it is imperative that the missing grout (or putty; more on that later) be replaced.

Grouting by a tiler who probably installed many of the time bombs these situations represent (always check your references with the contractors you subscribe to as well as previous clients and you’ll find a great one) usually starts by trying to remove grout. We often see a razor blade/utility knife used to score the grout to hold the new grout. This process is doomed to fail, as the grout will look fine at first, but it will wash away. Much sooner than the owner wants it to be.

The tool we use to deeply remove the grout before re-grouting is our main advantage. The tools used to remove grout are crucial to doing a professional job. We use the Fein Multimaster to achieve a great result. A gentle oscillation removes the grout (without disturbing the tiles) and we can replace the grout in a way that will last much longer than any other method. Dust is kept to a minimum. We started using this method, after seeing how inefficiently grout and caulk are removed in most cases, leading to customer dissatisfaction when freshly skimmed grout disappears in a matter of months. Ineffective removal techniques include (trying to score the grout with a utility knife and just going through the old grout) are just efforts to make sure that at least some of what is applied sticks for a while.

Another important consideration when re-grouting is how the edges are treated. Edges and corners must be caulked. The grout begins to shrink as the water evaporates and cracks form. Putty contains latex or polyester instead of water, and this ensures (if applied correctly) that corners and edges don’t crack. Your installer may tell you that he has been grouting the edges for years and has never had a problem. We hear this all the time as we estimate showers with cracked grout in the corners. I suspect that the reasons for not caulking are twofold: 1- the trouble one must take to acquire the caulking that matches the needed color of the grout 2- the caulking technique requires patience which not everyone has.

The first place we usually start in the grouting process is to match the color of the existing grout, as it is only the rare circumstance where we will have to remove all of the grout. This can be a problem in some cases and if necessary we can apply a colored seal to the grout to achieve a consistent look.