This sleek and functional concrete countertop is a stylish way to give your deck, patio or gardening space a convenient outdoor kitchen. With some Quikrete products and a little know-how, you can complete this project over the course of a few days.
Noted DIY blogger Ben Uyeda, of HomeMade Modern, created this concrete countertop project for our DIY Challenge here on The Home Depot Blog. We asked him to come up with a practical DIY project using concrete.
Follow along as he builds this amazing outdoor kitchen.
DIY Outdoor Kitchen with Concrete Countertops
- ¾ in. Melamine
- Quikrete Countertop Mix “Grey”
- Silicone Caulk
- Steel Mesh
- Penetrating sealer
- Quikrete Liquid cement color
- Concrete Blocks
- Quikrete Fast-Setting Concrete Mix
- Quikwall surface bonding cement
- Cordless Drill
- Table Saw
- Compound miter saw
- Orbital sander
- Circular saw
Step 1: Cut the melamine
I used my table saw to rip down strips of melamine that are 4 in. wide and 2 in. wide. The 4 in. strips will be used for the countertop and the 2 in. wide strips for the sink.
Two inches is not very deep for a sink and you can cut wider strips to make it deeper. But I recommend the countertop strips being at least 2 inches wider than the sink strips, using a miter saw to cut the strips to length.
Step 2: Cut the bottom of the sink mold
I used my table saw to rip down a piece of dry erase board that I bought at the Home Depot. I picked this material because it’s thinner than the melamine, which means that there is less surface area along the edge that I will have to seal with silicone.
Step 3: Assemble the mold
I used my hot glue gun and scrap pieces of wood to assemble the mold for the countertop. I hot glued the melamine from the outside of the mold.
Step 4: Glue in the sink mold
I used my hot glue gun to glue the sink mold to the bottom of the countertop mold. I first glued down the 2 in. strips of melamine before gluing the piece of dry erase board on top of them.
Step 5: Glue on the drain
I used brass pipefittings for the sink drain and hot glued them to the center of the sink mold.
Step 6: Install the pipe for the faucet
I drilled a hole in the melamine where I wanted the faucet and inserted a series of brass pipes into the hole. Then I used my hot glue gun to glue the pipes in place.
Step 7: Seal the mold
I sealed the molds by squirting a bead of silicone caulk along the inside edges. Then I ran my finger along it to smooth it out and remove the excess.
I also used silicone to seal the exposed pieces of end grain on the melamine boards and dry ease board I used for the sink knockout. The finished mold should be sealed with silicone on the inside where it will come in contact with concrete. The outside should be sealed with hot glue.
Step 8: Prepare foam and wire reinforcement
I cut pieces of steel mesh that can fit inside the molds with about 3 in. to spare between the edges of the mesh and the edges of the molds. I then cut pieces of rigid foam insulation that will be embedded in the concrete to reduce the weight of the countertop.
I recommend having the countertops be no less than 2 in. thick in the thinnest area. I screwed the foam to scrap pieces of plywood and then screwed through the plywood and into the melamine mold to hold the foam in place.
Step 9: Mix liquid cement color
I want the concrete to be a nice dark grey so I premixed some Quikrete liquid cement color into the water used for mixing the concrete. I used about half a bottle of liquid cement color per gallon of water.
Step 10: Mix the concrete
I mixed one bag of Quikrete countertop at a time in a large mixing tray. I started by emptying the bag into the tray and then adding about ¾ of a gallon of the water that I had mixed with the liquid cement color.
I mixed the concrete with a hoe and added more water as needed. It’s helpful to have another person distribute the concrete while you mix.
I filled the molds ¾ of the way full, stopping periodically to use my hoe to push the concrete down into all the corners and edges.
Once the molds were 3 quarters full, I placed the steel mesh on top of the wet concrete and stuck the ends into the ridged insulation foam to hold it in place.
I then filled the molds the rest of the way. It’s important to get the concrete under the rigid foam.
Step 11: Screeding and vibrating
I used a 2×4 to screed the concrete. I pushed the 2×4 back and forth like a saw over the top of the concrete. I glued sanding pads to the melamine mold and then used my orbital sander to vibrate the molds.
You can also vibrate the concrete by hand with a stick. For past projects, I used my reciprocating saw with a piece of wood glued to the blade to vibrate bubbles out of the wet concrete.
Step 12: Cover and cure
I covered the concrete with a plastic drop cloth to keep it from drying out too fast. Every couple of hours we sprayed it with water and then recovered it to keep the concrete from flaking. We did this for the first 48 hours.
Step 13: Remove the molds
After letting the concrete cure for 4 full days, I cut away the hot glue and then pried away the melamine. I rotated the countertop back and forth to break the away the glue on the inside of the sink mold.
The countertop pivoted around the brass pipe I embedded for the faucet. Once the glue for the sink mold broke I was able to flip the countertop over.
Step 14: Remove the sink mold
I used my knife to pry out the hot glue around the faucet pipe.
I drilled holes in the edges of the melamine to weaken the sink mold before prying it out with a putty knife.
Step 15: Fill in the gaps
I didn’t vibrate the concrete enough so there where some air bubbles in the countertop. I mixed up a small batch of concrete and rubbed it into the surface.
Once that concrete had cured, I sanded the countertops smooth with 220 grit pads on my orbital sander.
Step 16: Build the base
I made the base out of 8 in. x 8 in. x 16 in. CMUs that are dry stacked and covered in 2 coats of Quikwall surface bonding cement. This not only provided a nice exterior surface, but it also has fiber reinforcement that strengthens the structure.
I started by placing the CMUs and checking to see if they were level.
I then mixed the Quikwall and applied about ½ in. of it under the CMUs. I adjusted the blocks until they were level with the help of some plastic shims.
Step 17: Seal the insides of the CMUs
Once the blocks were level, I sealed the bottom of the holes with more Quikwall.
Step 18: Dry stack the CMUs
I dry stacked the CMUs on top of each other until I had columns that were countertop height. Dry stacking is when you stack bricks or block without mortar in between. It’s fast and easy.
Step 19: Mix and pour structural cores
I poured some Quikrete fast-setting concrete mix into the cores of the CMUs and then added water on top.
I used a stick to mix it a little but this product mostly mixes itself when used in shallow applications. This isn’t a necessary step since the Quikwall coating is structural, but I wanted a little insurance since the countertop is quite heavy.
Step 20: Apply Quikwall to the outside of the columns
I wet the concrete blocks with a hose so that the plaster would stick better. Then I used a trowel to apply a layer of plaster that was between 1/8 in. and 1/4 in. thick.
Keep the concrete moist by spraying it every couple of hours with a fine mist from the hose. This helps to keep the cement moist as it cures to prevent cracking.
Step 21: Place the countertop
I let the Quikwall cure for 3 days before placing the concrete countertop. I used 2x3s as blocking so that we could get it into position with room for our fingers.
We then squirted in Quikrete anchoring epoxy on top of the CMUs before lifting the countertop, removing the 2x3s and lowering it into place.
Step 22: Build shelves
I used construction adhesive to glue galvanized L-brackets to the sides of the columns. Then I used duct tape to hold them in place while the adhesive cured.
I cut pieces of tropical hardwood decking and 2x4s with my miter saw. Then I screwed these pieces of wood together with stainless steel screws.
Step 23: Apply a finish coat of Quikwall
We applied a second coat of Quikwall because the first coat was a bit rough and we wanted to cover the upper parts of the L-brackets. Once that coat had cured we inserted the shelves.
Step 24: Make the faucet
I made the faucet out of brass pipefittings from the plumbing aisle of Home Depot. I checked to make sure the fittings were labeled lead-free and suitable for potable water.
I didn’t like the color of the handle on the spigot I bought, so I took it off and spray painted it. I assembled the pipes with pipe dope to ensure I had a nice seal.
Step 25: Seal the countertop
I used Quikrete waterproofing sealer to seal the concrete countertops. I applied it with a foam brush. One coat was all I needed to make water beads fall right off the surface.
Step 26: Finishing up
I attached a 2-way hose splitter to the spigot so that I could run a garden hose for watering my plants without disconnecting the faucet.
I used a short piece of hose for a drain and placed a watering can underneath it so that I can reclaim the water from the sink.
Ben Uyeda is a designer, lecturer, and entrepreneur focusing on the field of affordable and sustainable design. Ben is the co-founder and design director of FreeGreen.com, as well as a visiting Lecturer at Northeastern University. See his designs and DIY projects on his blog, HomeMade Modern.