Let’s talk about grout. With our penny rounds finally all installed, grouting was the next step. That final step transforms a project from “in progress” to “completely finished” — and it makes a huge visual difference.
Here’s how we tackled the grouting process, and what we learned along the way.
First, the materials we used:
- Bucket of clean water
- Putty knife and a separate bucket for mixing grout
- Paper towels — grout is messy
- Sanded grout in the Mobe Pearl color
- Rubber grout float
- Flexible grout admixture to reduce shrinkage and cracking
- Sponge for cleaning and smoothing
We also used leftover rosin paper to protect counters and make cleanup easier. Grout, like thinset, should be mixed in small batches because it begins to dry within 20–30 minutes. We added the admixture first, then the grout powder, following the directions for workability.
I mixed with a putty knife until the grout reached a toothpaste-like consistency — firm but spreadable. That texture makes it easy to press grout into the joints without making a runny mess.
Grouting felt almost meditative after the concentration it took to install the penny tile. The main motion is simple: use the rubber float to push grout into the gaps, then scrape off the excess while holding the float at an angle. One person can do it, but it’s quicker with a helper.
After filling the joints and removing excess, the sponge-and-water step is key. Dampen the sponge and gently wipe the tile surface to remove grout haze and to smooth the grout lines. This step both cleans and refines the finish; it’s simple but surprisingly effective.
We filmed a short one-take video of the process — short because life happened — but the main actions are easy to follow: mix, float, scrape, sponge, and repeat until the area is grouted. The work is a bit tedious and can tire your wrist, but the results are worth the effort, and we completed the whole room in an afternoon.
The transformation from ungrouted to grouted tile is dramatic. Dried grout lightens up compared with wet grout, and once any haze is buffed away the tiles really gleam. In our case the grout also tied together the varying tones in the penny tile and made the whole surface read as a cohesive backsplash rather than a patchwork.
We also caulked corners and seams where tile meets other surfaces, using a caulk color matched to the grout. Caulking creates a finished edge and helps prevent cracking at transitions. In the photo we took during drying, the caulk looked darker at the seam; that lightened as it cured and after a final buff.
From farther away the tiled area reads as a subtle pattern rather than a single block of color, which was exactly what we wanted. The individual penny tiles and their slight tonal variations remain visible even from the frame hallway and from the front door, so all the hours of installation paid off.
Close-up views show the charm of the tile: some discs are a bit darker, some have a ring or semi-ring, and the natural variation adds dimension. When paired with a similarly toned grout, those variations look intentional and refined, producing an almost marble-like effect without the cost.
We worried grouting might highlight imperfections in how the sheets were laid, but the low-contrast grout actually helped minimize minor inconsistencies. If you choose a high-contrast grout, seams and alignment mistakes become more noticeable. A like-toned grout can bridge small gaps and make the installation look neater overall.
Next steps for this project include sealing the grout to protect it and performing a final buff to remove any remaining haze. The Tile Shop sells haze remover products, but often a dry cloth and some elbow grease do the job well. After sealing, the backsplash will be easier to keep clean and will maintain its polished look.
We’ll share updates as we seal the grout, finalize lighting, install the range hood, and add open shelves. Have you grouted before? Some people find it satisfying — for us it was worth it in the end. The finished penny tile backsplash is one of those small projects that delivers big visual payoff.
Psst — our most enthusiastic indoor train rider stole a few scenes during the project. More on that in another post.