Is Flat Pebble Mosaic on the Shower Floor a Good Idea? Consider This…
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Would I install flat pebble mosaic on the shower floor again?
In some of my last few YouTube videos and in past blog posts you may have noticed I installed a flat pebble mosaic on the shower floor in my master bathroom. I’ve recently been asked if I would choose that kind of flooring again.
In short, no.
Before I go into the why-not’s, I want to preface this with it may depend on the stone/style you choose. There are some beautiful cut river rock mosaics that do not have some of the problems I encountered in my shower. YMMV. The end goal for this post is for you to take this advice and apply it to whatever mosaic you are considering.
Considerations AGAINST installing a flat pebble mosaic on a shower floor:
#1 Flat pebble mosaic may not be as flat as you think it is.
It might look flat in the box, but look harder. Do you see some differences in height?
Are all the rocks cut even across the entire stone?
Real life test: Take a coin and try sliding it across stones.
Sometimes it is even more obvious:
While it doesn’t happen often, on some of the less fabricated and more natural kinds of cut rock mosaic may have some proud points.
If it is not flat across the mosaic, this makes a difference for two reasons.
Reason #1: It is more difficult to install.
During the install you may end up taking off more than a few stones to add additional mortar to the back. It’s a slow and painful way of disassembling the stones off of the mesh backing of the mosaic. The whole point of the mosaic is to make installation easier. Once you realize a piece has already down but it doesn’t have the correct height then you start jacking around with pulling the stone off of the mesh, which ends up messing with the stones around it…you get the idea. An imperfect mosaic very much complicates a simple act of laying down tile.
It is inevitable that there will be some differences in height once it has been mortared into place. This causes difficulty of the grouting process. You’re trying to level out the grout in between the dissimilar stones. Do not use any quick set grout during this process or you will hate life.
Reason #2: Water drainage may become a problem.
If you do not maintain a perfect slope* going straight to the drain you are going to end up with pools of water at the end of every shower.
*We are assuming at this point at your shower pan is already properly sloped and whatever waterproof membrane is also installed maintaining this slope. So all your tile has to do is maintain the same slope.
It is easy to create a low spot when installing flat pebble mosaic on a shower floor, creating improper drainage.
Why is this a problem?
Because water in the wrong place over a long period only needs time to cause a problem in the shower. Maybe it starts as a stain. Next it could break down the grout. Or perhaps the grout allows water to pass through, leading to a pool of water forming under the tile causing it to pop up.
How do you get rid of the standing water?
- Rely on evaporation and / or
- Rely on the grout to allow the water to seep down below and then you are relying on the waterproofing membrane below to stand up to constant water.
When this happens all you have to do is start a stopwatch to see how many months or years it takes for the shower floor to fail.
Maybe this isn’t a big deal if you live in a very dry environment. Even if you do live in a humid environment your HVAC system may remove enough of the humidity through air conditioning in the summer and heat in the winter.
Another few questions along those lines that only you can answer:
- How often will you use this shower?
- Is it in constant use in the morning and evening?
- Or is it more of a showpiece and you limit yourself to one shower in the house to cut down on cleaning?
#2 There is a significant amount of grout on the floor with this kind of flooring.
Flat pebble mosaic requires significantly more grout in comparison to a 2″ x 2″ square mosaic or anything larger.
As noted in the previous point, grout is porous (as we also captured in photos in this post: Do You Need to Remove Tile After a Flood? Solved!).
#3 A flat pebble mosaic may have lines.
When I think of a flat pebble mosaic, I imagine sitting along a bubbling creek. The water meanders down a valley with no rhyme or reason other than taking the path of least resistance. There are certainly no straight lines associated with the natural flow of water.
However, flat pebble mosaic comes in a box in order for it to sit on a shelf at the store and arrive at your shower intact. On top of that requirement, is it also must interlock. This results in a repeated pattern.
Will lines bother you?
They bothered me and, admittedly, I had really hoped that filling it in with grout would make it less obvious. I was wrong.
If anything, I think it makes it look more obvious. The lighter colored grout juxtaposed against the dark stones highlights the lines. Maybe using a grout closer to the color of the stones would make the lines less obvious, but in my case it is what it is now.
You can also take the time to take some of the outside pieces apart and rearrange them so that the joints are less glaring. This, obviously, will make the installation take longer.
While I was unsure of the effect of the grout, I did actually rearrange many of the stones around the drain. I figured I would be more likely to look down at the drain below the shower head, so that extra time was well spent making that area look a little more like what I had originally hoped.
This is one of those items that depends on the mosaic you choose. Some interlock much better than others.
Real life test: Take several pieces of the flat pebble mosaic in line them up on the showroom floor.
A shower pan is often not flat.
I’m not talking about the quality of the shower pan sloping into the drain. Let’s assume at this point it is perfect or as close to perfect as possible.
If you are installing a traditional drain somewhere in the middle of the shower, then the shower pan will have four slight angles that impact the square mosaic.
You can’t fight geometry.
Even when you line up the mosaics on the showroom floor, remember your preview is on a flat surface and the shower floor is at an angle…meeting an angle.
Keep this in mind as you view the pictures below because you’ll notice a display on a showroom floor does not have a drain–or a properly sloped shower pan!
This might be a great argument for a linear drain at one end of the shower, if you were already considering one.
If you would like to see these considerations “in person” check out the following video:
Sample photos of different flat pebble mosaic laid out, grouted displays, and demo showers for your perusal:
As promised in the video above…
I took my own advice and lined up several pieces of each mosaic at Floor & Decor–a place many have access to along with reasonable prices. Most tiles are in a plastic wrap. Since I wasn’t an actual customer buying these I didn’t feel comfortable taking off the wrap to give you a better picture. However, you can still take a peek and estimate where you think the stones actually meet.
I also took photos of the displays so you could see what it looks like on a flat surface. Notice some of the displays are only two pieces and look like they work well together. But it is only two pieces. If I were making a display to sell product with only two pieces, I’d probably go through the stack to find the two pieces that matched perfectly…or rearrange some stones. Just being honest about what I would do in that situation. Although the same logic should be applied when determining how pieces are laid out on YOUR shower floor.
Related post: The Difference Between a Good vs Bad Tile Job
As for the permanent showroom floor inspirational bathroom ideas, many of the mosaics are no longer offered. My shower tile, for instance, is photographed in a display, but no longer sold there. It does give you an idea that the current manufacturers of flat pebble mosaics on the market today may have noticed the problems with the pattern and are now offering an improved version.
You be the judge…
So now the game is kinda like Where’s Waldo: Where is the edge of each flat pebble mosaic?
**Just as a reminder, you can always click on the pictures to get a larger version.**
Layout Tests:
This mixed grey mosaic looks promising.
The joint meets at several points, but there could still be some gaps that occur more regularly. However, the stone placement is a good, irregular pattern.
Mixed medium brown flat pebble mosaic sample line up.
The joint meets at several points, but there could still be some gaps that occur more regularly. The stone placement looks slightly more regular along the outside.
That one stone jumped out at me as it actually touched despite the plastic wrap. So does the second set of tiles to the right.
Grey flat pebble mosaic sample line up.
The seams are excellent and the stone pattern matches inside and along the edges. It is interesting to note there is some breakage where the stones met since the stones are not tumbled, but more of a rectified edge.
Mixed brown flat pebble mosaic sample line up.
This one is the package deal. Varied stone placement and an excellent hidden seam.
This is a contender!
I had this photo from another store and did not lay them out as I did during a subsequent visit specifically for this post. However, it is another excellent sample where the seam is hidden and the stones have a good randomized pattern. Unlike the grey example above, despite the fact these stones are rectified and not tumbled, there is no sign of wear between stones.
Sample “Showers”
Take note how much difference there is between a single line of mosaic in comparison to multiple “tiles” surrounding each other.
Mixed medium brown flat pebble mosaic on a shower wall.
Mixed medium brown flat pebble mosaic on the “shower” floor. Again, notice the lack of drain or sloped shower pan.
The matching light grout helps hide any obvious gaps and lines along this 2′ strip of flat pebble mosaic on this display shower wall.
The wear on the floor has discolored the matching light grout. As a result, the pattern is a little more obvious on the shower floor than it is on the wall.
Despite the difference in grout color, this rock mosaic is REALLY well hidden.
Hmmm…it looks like I wasn’t the only one who had a shower floor look like this. 😉
Product Displays
Flat pebble mosaic two tile product display. The pictures of the mosaics shown on the floor above are more of these three products. Can you find the lines?
Grey cut river rock mosaic product display. Can you find the two horizontal lines? I was surprised I didn’t see any obvious seams going vertical.
Is flat pebble mosaic for you?
All of these considerations should be taken into account when you are making your final decision on floor tile. If you have your heart set on a flat pebble mosaic just know this going in.
It’s not to say that flat pebble mosaic is a bad choice for your entire shower. It is gorgeous tile! It would be fine for any vertical surface where water is not allowed to pool.
This is definitely one of those subjects where you might not have the luxury of experience, but it only with experience where you find out you don’t like something. We just can’t know everything when it comes to the wrong product for a certain application. So hopefully this post helps you decide if a flat pebble mosaic is still a contender for your shower floor.
