How are concrete countertops made?

Making concrete countertops involves several processes: choosing or making your own concrete mix; constructing the concrete countertop mold; pouring your concrete mixture into the mold; slurrying and grinding; and waxing and sealing.

Concrete countertops can be made by professional builders or by do-it-yourself homemakers who are looking for a new project to do. Unlike natural countertop materials like granite, soapstone, or limestone, concrete is not quarried from the earth. Instead, it is made by mixing sand, water, and cement. These materials can be hand or machine-mixed, depending on how much concrete you intend to produce.

Making the concrete mix

Concrete countertop mixes can be made from scratch or can be bought from professional builders. To make a concrete mix from scratch, mix cement, sand, and water together by hand or by using a cement mixer. You need to use a cement mixer if you intend to make a large batch of concrete mix. The commercially available countertop mixes are usually made of a water reducer, admixture, and pigment.

Constructing the countertop mold

After you have made your concrete mixture, you are now ready to construct your countertop mold. Countertop molds are made of different materials, and they serve as the pattern for your kitchen countertop. They contain all the inserts and holes for your kitchen equipment and other built-in structures like sinks.

Pouring the concrete mix into the countertop mold

The concrete mixture is then poured into the countertop mold. This step can take some time because the consistency is regularly checked in this stage. The concrete mixture has to have the right thickness to be able to hold well and take the shape of your mold. In this step, the color pigments can be added to achieve the desired shade. Other effects like marbling and veining can also be achieved in the pouring process. They should be worked in the cement before it becomes dry and hard.

Slurrying and grinding

The slurrying and grinding of concrete countertops is done after the mixture has set into the mold. Slurrying and grinding is not a necessary process, but is often done for aesthetic purposes only. If you are already happy with the results of your mold, then you no longer need to polish and finish your countertop. Without slurring and grinding, your countertops can look a bit rustic and unfinished, a look that some people prefer for their countertops.

Waxing and sealing

Waxing and sealing is a step that must always be performed. It makes your concrete countertops smooth and shiny, and it also protects your newly-made countertops from cracking and breaking easily. Sealants are applied at least a day after the concrete countertop has completely set and dried. This allows the sealant to penetrate into the concrete without discoloring the surface.