After my tile-laying extravaganza, the remaining tasks—grouting and sealing—seemed small by comparison. I had taken the entire week between Christmas and New Year’s off and planned several days to finish them, yet I found myself dreading the grouting. My dad called it “the pits,” and friends admitted it was the hardest part of tiling for them. Even a helpful employee at the home improvement store hinted it wouldn’t be pleasant. Couldn’t we just leave the tiles as they were?
Eventually I accepted that it had to be done. I’d already postponed twice: once because I misread the mixing instructions and accidentally used far too much water, and once because an unexpected car accident delayed my day. Those setbacks turned out to be fortunate. Before we started demo, we’d already bought grout from a big-box store—nonsanded Polyblend in “bright white” for the shower and “nutmeg” for the floor. Nonsanded grout is recommended for 1/16″ grout lines and won’t scratch marble, so it seemed like the right choice. But over the break we were advised to check a specialty tile store for longer-lasting, more mildew-resistant grout and a wider color selection.
The specialty store did not disappoint. Their color selection was far superior and they provided actual grout samples so we could hold the grout next to the tile and see how the tones matched in real life instead of relying on a colored label. We ended up swapping the bright white for a subtler “standard white” that matched our tiles more closely, and replaced the red-tinged “nutmeg” with a truer brown “mocha.” Best of all, the specialty grout cost the same as our original choice. In hindsight, we were glad we hadn’t used the original colors, which would have made the shower grout unnaturally stark and the floor grout too ruddy.
Once the tiles had at least two days to set, I gathered my supplies—most inherited from my dad’s past projects—and prepared to grout. My kit included:
- a grout float
- sponges
- two buckets (one for grout, one for clean water)
- paper towels and rags
- Flexible grout admixture
- grout release
- marble sealer
Before mixing grout, I prepped the surfaces with grout release on the shower walls and sealer on the marble floor. The grout release acts like a non-stick layer, making excess grout easier to remove from tile faces, while the marble sealer both protects the stone and later doubles as a grout sealer.
This time I followed the instructions carefully and mixed the correct ratio of liquid and powder into a toothpaste-like consistency. Instead of plain water, I used Flexible Grout Admixture as recommended with our grout. It helps reduce shrinking, cracking, and discoloration over time, so it seemed well worth using.
Mixing by hand isn’t glamorous and several people warned it would be unpleasant, but it wasn’t as bad as I expected. I measured out an amount of grout I could reasonably use in about 25 minutes (to avoid drying out), added the admixture, and mixed with a paint stir stick. After working the mixture until smooth and letting it sit for ten minutes as directed, I remixed and began applying it with the grout float.
The grout float—basically a rubber trowel—made spreading the grout straightforward. I picked up small amounts and pressed them firmly into the narrow grout lines, holding the float nearly flat so the grout packed fully into the joints. With 1/16″ grout lines, filling was quick, though firm pressure was essential. I then tilted the float to about 45 degrees to scrape away excess from the tile faces.
After eight to ten minutes of grouting, I used a lightly damp sponge to remove the remaining residue and to smooth the grout lines. The key here is lightness: a barely damp sponge and gentle passes. Keeping the sponge clean and refreshing the rinse water frequently prevented smearing and helped remove the bulk of the excess. The previously applied grout release likely made this step easier, but regardless, the process moved along far more smoothly than I’d feared.
Grouting the entire shower was a bit repetitive and tiring, and I stopped occasionally to clean tools and mix fresh grout—ultimately using about 3 pounds from a 5-pound container for the tub and surround. When the shower was finished, the transformation was impressive: the white grout filled the dark negative spaces and shifted attention back to the tiles themselves.
Grouting the floor was faster. The darker color required more careful mixing for consistent shade, but because the tiles were larger and grout lines minimal, I used only about 1.5 pounds. The contrast reduction and clean lines made a dramatic difference.
After the initial sponging, a light haze—grout film—remained on the tile surfaces. I tried additional damp sponging and the pre-sealed marble did help, but the haze still lingered. Hesitant to apply more chemicals, I instead used dry paper towels with a bit of elbow grease; repeated dry wiping removed the residual haze from both the shower walls and the floor. A simple finger test confirmed there was no remaining film.
We let the grout cure for 48 hours before sealing; an accidental water incident pushed our cure time to about 72 hours, which only made us more confident in the results. Sealing was a simple final step: I applied several coats of marble sealer to the floor and a grout sealer called SurfaceGard on the tub and shower surround. Sealing darkened the grout slightly, which helped it blend with the mocha tones in the tile.
Once sealed, the room almost felt shower-ready—fixtures and final caulking were the only things left. In the end, grouting wasn’t as miserable as I had feared. Good color choices, proper preparation, and careful mixing and cleanup made all the difference. The finished surfaces looked clean, cohesive, and durable, and the extra time we took to select the right grout paid off.