DIY Concrete Countertops: Tips, Tricks and What NOT to Do

Let’s talk about concrete projects.

No, not just projects that exist in the real world – which is true here – but actual concrete. You know, cement, sand and water.

If you want to learn more about concrete countertops, this is the post for you.

As we prepared to get our Texas house ready to sell, we wanted to refresh our kitchen.

My Fix It Farmer repaired cabinets and I painted them a creamy white to cover the 1990s pickled oak. I also removed what felt like acres of wallpaper and textured, patched and painted the walls and ceiling.

And we opted to replace a lot of elements that were damaged and/or outdated: the backsplash, the fluorescent lights in the ceiling, the cooktop, an oven that may or may not be cursed, and even the kitchen sink.

But the biggest endeavor of them all was our decision to replace our stained and chipped white formica with concrete coutertops.

In hindsight, not gonna lie, I greatly underestimated the complexity of this project. This is not one to be entered into lightly because, you know, concrete is heavy.

In this post, I’m not going to give you step-by-step instructions. Here are some great resources that do just that:

• Concrete Countertop Solutions main instructional video.  This is the main resource we used because it shows pretty much every step of the process.
• Bourbon Moth Concrete Countertop DIY . We found several helpful tips in this one, like reinforcing the top over a long span.
• What the Flip How to do Concrete Countertops. They talked about timing, which is critical.

Instead, I’ve got tips to help you succeed in pouring and finishing your own concrete countertops. And even more important, mistakes to avoid.

The product

The most common way for DIYers to do concrete countertops is by using Z Counterform Solutions from Concrete Countertop Solutions, a pour-in-place system that comes with plastic forms that create the edges.

Views of the half bullnose plastic forms and finished edge.

The company offers more than half a dozen options for different looks, from the 90-degree square form to a double fancy radius form with multiple bevels and a curve.

The more complex the form, the more prone they are to air bubbles that either add “natural character” to your edges or must be patched after the concrete dries.

We went with the half bullnose, which has one curve and no bevels. The kit also comes with a flat back edge, which goes along the wall.

You need 1/2-inch thick concrete backer board that you attach to the top of the cabinets with backer board screws. If you have a large cabinet, you may need to use a 2×4 inset in the middle of the span to support that stretch of concrete.

The plastic forms are screwed to the backer board with steel 5/8 inch screws.

Here’s a countertop form with the mesh and Z Clips in place. The area with no mesh is the cutout for the sink.

You also need the fiber mesh reinforcement, which acts like rebar in concrete to give it added strength. Z Counterform also offers Z Clips that look like the plastic piece that keeps the pizza box from sticking to the hot cheese. Once screwed to the backer board, the clips support the mesh at regular intervals to suspend it in the middle of the concrete.

The key part of Z Counterform is their LiquiCrete, a powder you add to the concrete to make it flow better and have a smooth finish.

Each box of LiquiCrete gets mixed with a 60-pound bag of sand topping mix concrete and a sometimes varying amount of water, depending on environmental conditions. We typically used about 6 quarts.

One other thing we added was a white colorant to lighten the countertop from a medium gray to a light gray. Here is where I think we made a strategic error that would cause me many hours of work and frustration. More on that later.

You’ll also want some kind of sealer to keep the countertops from staining and make them easy to clean. We used Z Aqua Poxy.

The Tools, Part 1

Here’s what you’ll need for the pour:

• two 5-gallon buckets (one for mixing concrete and one partially filled with water to soak your
  

  Use a steel trowel to smooth the surface of the counter.

  concrete-laden paddle bit)

• powerful drill with paddle bit
• trowels for scraping concre the bucket and for filling the forms
• long scree tool to evenly fill the forms (make one from a straight edge or 2×4 or buy one)
• containers of pre-measured water
• magnesium float for first finishing pass
• steel float for final finishing and polishing
• device for tapping the edge of the forms to minimize air bubbles (could be a heavy handle or an orbital sander)
• spray bottle to keep your trowel moist

The timing

When you’re working with concrete, time is of the essence. You don’t want the concrete to get too dry before finishing AND you don’t want to start finishing too early.

Also, when you’re pouring six or more batches in a day, you don’t want any big delays that result in one batch drying out more than the batch next to it.

Also, the troweling process takes time and several passes to get it as smooth as you can. You can use a spray bottle to keep the trowel wet and gliding smoothly.

The team

Don’t attempt this on your own. Just don’t. I watched a time-lapse video of a guy doing it all by himself, but I don’t know how that worked. The aforementioned timing will bite you in the gut.

You need a minimum of two people: one to mix and one to fill the forms, tap edges and smooth the surface. If you’re doing a large expanse of counters, three people is ideal because your first batch will be ready for floating and finishing by the time you get four or more batches into the process.

The scree we used to evenly fill the forms was a 4-foot metal straight edge. We also used a metal yardstick, but the concrete wore off the numbers.

We did three big pours: the counter that included the sink, the opposite counter that included the cooktop, and the high counter above the cooktop counter that provides a bar area and separation from the family room.

We had Shawn’s dad John, the OG Fix-It Farmer, help us with the first and last pours. They both went sooooooooo much better than the middle pour.

Part of it might have been all his experience in concrete, although he’d never done counters before. And part of it was just his calming, can-do presence.

Shawn mixed batches while John and I filled forms, tapped edges, and floated and troweled the surface. The pour when it was just Shawn and me ended up with batches getting too dry before they were finished and made the surface super difficult to smooth.

You need a magnesium float for the initial smoothing of the surface. It brings the moisture in the concrete to the surface. Follow this up with the steel trowel for a smoother finish after waiting for the surface to get more firm.

Test pours

Before we attempted the big pours, we did two test pours with a single bag of concrete and one bag of Liquicrete, which made a tall table for the patio and a small island for the kitchen. Each batch did about a foot and a half in linear feet of counter (about 18×24 inches).

We intentionally made the tables smaller than the full batch, just in case of spillage or miscalculations. With the remaining concrete we filled plastic forms using the bowls from Healthy Choice Steamers. The Fix-It Farmer finds these plastic bowls endlessly useful, thus we have hundreds of them stored in various locations.

From keeping a small plate or bowl of food from splattering in the microwave to storing odd screws, they do have some utility.

The HCS bowl-shaped concrete served the function of allowing me to test out sanding, patching and sealing small portions of concrete, which brings me to the next step.

Finishing and Tools, Part 2

Here’s what you’ll need to bring your countertops to the finish line:

• Patching compound
• Disposable gloves
• Sandpaper of various grits
• Orbital sander or use your hands
• Putty knife
• Sealer
• Good quality roller (velour is recommended)
• Foam brushes
• Tack clothes

No matter how careful you are, you likely will have a few air bubbles in the edges and the odd divet or crack in the surface.

This is where you use Countertop Solutions’ CounterPatch, a patching compound designed for just those instances.

I’m patching small holes in the countertop edge with Z Countertop Solutions special patching compound.

Put on your disposable gloves and slap some patch on those holes, or you can use a putty knife. You try to overfill the curved edges so when you come back and lightly sand the surface, you get back to smooth.

This is also where I encountered a lot of issues, primarily because of the colorant I used in the original pour. The white colorant didn’t look the same in the patching compound as it did in the main pour. No matter what I did, the patch was darker than the main pour.

In a normal pour, you may have some variation in color. The first counter had the most variation and the last had the least. I think environmental factors can impact the way it looks when cured.

The patched areas really stood out to me, so I ended up using more patching compound to hit other areas on the counter to make it look like a feature instead of a bug.

The one place this did not work was the spot on the high counter.

After the final pour cured and I brushed on a coat of sealer, I noticed one of my hairs stuck in the concrete. You could see it up close or from just the right angle.

Light sanding didn’t work to remove all of it, so I had to go after it with several rounds of sanding.

Then there was an obvious uneven spot in the counter about the size of a baseball.

So I got out the patching compound, mixed it with the white colorant we used to lighten the color of the counter, and smoothed it out. But when dry and sealed, it was noticeable darker than the rest of the counter.

I’ve sanded, patched and sealed the area 4-5 times, and I’m still not happy with it. I don’t know whether to blame the patching compound or the colorant. I’m leaning toward the colorant.

If I’d gone with no added color or with the Countertop Solutions special white mix and patch, the match probably would have been fine.

Since I painted our cabinets white, I should have just gone with the plain gray cement mix, no added colorant.

To sand or not to sand and a few things to avoid

The first pour had a number of uneven spots and required quite a bit of sanding, especially after patching. You can sand by hand or use an orbital sander. I used both: the power sander for the worst areas on the first pass and hand sanding for other areas and subsequent passes.

Some folks prefer sanding the whole top because it exposes more of the aggregate in the concrete, but I was going for a more smooth look.

You also sand the whole top if you’re staining the top a different color, so it will better accept the stain.

After getting the top as smooth as I could, I cleaned off the dust and commenced with sealing.

I used both a roller and foam brush to smooth out the sealer.

The glossy sealer we used came in two bottles, and I mixed equal parts from each. Then I brushed on a light coat. The instructional video used a velour roller to roll on the sealer, and I used that to get good coverage, but it left tiny bubbles in the surface. I found that lightly going over the area with a foam brush after the roller smoothed it out.

You let the sealer dry for at least 12 hours, then sand very lightly and apply another coat. The instructions recommend three coats. I applied five or six because it just wasn’t smooth enough for me at three.

If I had it to do over again, I’d go with a matte finish. I think the flaws would be less glaring on a matte surface.

Our first countertop pour required resealing after a year of use because it had a few tiny spots where the coats of sealer came off.

Then there was the tape fiasco.

When I retiled the backsplash, I put blue painter’s tape where the counter met the wall. Big mistake. The Countertop Solutions instructions tell you not to use any type of tape on the surface because it pulls off the sealer.

So yeah, I had to reapply multiple coats of sealer along the walls.

As far as maintenance goes, I use cleaners that are appropriate for stone to baby the sealer. Don’t use anything too harsh or abrasive.

My conclusion: I would think very hard before doing concrete counters in another kitchen, unless it was an outdoor kitchen.

They are not an easy DIY project, no matter what those YouTube videos imply. They require many hours of work beyond just the pour.

If I did them again, I would either use no colorant or their white mix. And I would use matte sealer. I would avoid tape and, this is important, wear a hairnet.

Here’s the finished product. All in all, it’s a good looking counter.

Want more DIYS? Here ya go:

Budget hacks for removing wallpaper

Texturing walls with a paint roller

Tiling a large shower