Grouting a Beach Stone Floor (Part 2 of 2)

For Part 1, start here.

It was really a pleasant surprise to find that shale makes a kick ass floor. The big box full of rocks sat in the back of the garage for at least 9-months before I got the courage to try it out in a real-life installation, the idea of a disastrous floor shook me to the core. But who knew that a fragile, common beach stone could be this incredible?

Really, this post is mostly about my unfiltered amazement and happiness, secondarily about how to grout a hand-mounted rock tile floor. I try and do a lot of DIY projects that push me and my abilities, but by taking this opporunity to mix up the entryway, I took a big non-reversible risk, because chiseling mortar off cement to repair the original floor would have been impossible. Oh, and I chose the most fragile rocks that line the Lake Erie beaches, since most pieces of shale are breakable by hand (these aren’t like nice round pebbles, they’re good skipping stones). And I did it totally for f-r-e-e, not heading to the store for a single item. All in all, I spent days (4-ish days) with my hands soaked with mortar and grout, which means now I need to spend the next 4 days rehydrating and soaking myself in moisturizer because those substances will suck you dry. No exaggeration, I’m still a prune, but a prune with a very unique entryway that adds a lot of character to the house. Most homeowners don’t mess with stone entryways, especially shale, because they require a good deal more involvement than wood or even tile,  but I’m glad I tried it myself because the only other options would likely have been to hire a contractor, work with a custom home builder that also offers interior design (example: Ryan Homes), or live with the floor that we had.

I outlined Part 1, the work I had done in installing the shale into mortar on the entryway floor, with promise to come back and show you how wonderful it would look with some dark grout locked solidly between the stones. I chose a dark Pewter gray, which is the grout we used between the subway tiles in the shower, mostly because a half-bag was already sitting in my basement waiting for the next project, just enough to grout a thick stony entryway. Bonus: Because it’s our main entryway,  a lot of dirt gets tracked through. Dark grout won’t stain so obviously and will look cleaner in the long run, yo.

I started off grouting day with a few simple tools:

• A bucket, filled with about 2-3 cups of mixed sanded grout (I never mixed more than that at once because it dries up really fast)
• A grout float
• A small trowel
• A bucket full of water
• A large sponge
• And rags. Lots of rags. Luckily, I have a lot to burn through.

I grouted the floor much like grouting any traditionally manufactured tiles, by using the float to mash grout between each tile, and wiping it over the surface of the stones without letting the edges dig into the fresh grout lines. The stones had cured in the mortar for 4 days at this point, I wasn’t taking any chances by grouting before the mortar had a good chance to harden. I had been nervous about the mortar taking longer to dry since it was applied over a non-porous cement surface, but it shown no obvious signs of moisture or mushiness after 4 days. Mushiness is a word for describing the hardening process of mortar, right?

It may have been laid on pretty thick, but the gaps between stones were easily between 1/8-1/4″ in depth, with upwards of 1/2″ wide in some spots. I moved in small batches, because getting the grout into the many spaces took longer than you’d think (multiple hours for the 20 sq. ft. space). Oh yeah, and those socks were trashed. Big crunchy grout traps.

Some areas sat undisturbed while I worked on grouting other sections, but after each area sat for 30 minutes, I began going back over the settled grout, wiping it down slowly with the damp sponge (rinsing the sponge off in the tray of water as I went along). It was going to take a long, long time to clean it all off. Where I’m pointing, I’ve already wiped it down twice.

And when I say this whole process took a long time, I mean days, but that’s not to dissuade you from trying it yourself. Even after I wiped it down twice with clean water and a clean-not-sandy sponge, it was still pretty gritty. Grout’s messy, what else can I say, that’s your fair warning.

I cleaned the surface as gently and as best as I could before my arm wimped out on me, and then left the floor alone overnight to dry completely. The following morning, I had better luck going back over every single stone and cleaning the surfaces individually, by hand, with a damp rag, followed by a dry fluffy rag to pick up the last of the loose bits. Tired hand again, I waited a few hours for the remaining moisture to evaporate and then snapped these pictures. Pretty, right?

Up close and from afar, it looks great, and underfoot, it’s wonderful. I do notice that there are wee bits of grout on every uneven surface of each rock, I partially suspect that it’ll wear away over time with sweeping and wipe-downs, but if it is locked on in some spots, no big deal. It’s natural rock, I’m not that worried about it. For those who asked, we are leaving it unglazed but I do have good intentions of going back over the surface with a grout sealant that helps waterproof the grout a little bit and mostly prevents staining.

The shot that I usually take from the living room looking into the entryway really takes the cake though. I love how it looks with the shiplap wall and the purple door. Bonus, I just hung the good ol’ driftwood wreath back up to celebrate the start of spring.

Hope you like it and are inspired a little to try this simple DIY in your own homes!

If you missed the post on how to install shale stone tile, you can backtrack to it by clicking here.