How to Lay Concrete on Top of Formica

A kitchen with Formica countertops.
What You'll Need
Cardboard boxes for patterns
Concrete board
Table saw
Concrete sealant

Most new-build homes come with Formica countertops. You might want to lay a concrete countertop over the Formica surface. Formica surfaces will usually cost thousands of dollars to lay an entire kitchen, and granite fabrics can cost even more. Concrete countertops, on the other hand, may cost as little as $500. Concrete can be shaped and molded to fit any kind of counter, and it can be styled to create a much more attractive appearance than any standard Formica tops.

Step 1 - Measure the Countertops

Find a couple of large cardboard boxes. Refrigerator boxes are suitable for this. Measure your Formica countertops, and then lay your patterns on top of the counters. Cut them into the pattern of the Formica tops to ensure that the concrete will fit securely on top of the Formica.

Step 2 - Cut the Concrete Board

Using the cardboard as a cut-out pattern, cut concrete board to the shape of the countertops. You may need to use a power tool such as a table saw to cut the concrete boards into the right shape. While you are cutting the board, remember to include fittings and fixtures such as sinks and kitchen taps.

Step 3 - Mix Your Concrete

For a darker countertop, mix high-strength concrete with reinforced fiber. For a lighter countertop, use something such as a white Portland cement. You will be able to find both of these mixes in your local home improvement store. You will need roughly one box of concrete dye for every bag of cement.

Step 4 - Cover the Boards

Once the concrete is mixed, cover the concrete board with it, and pound on the covers to ensure that air bubbles are eliminated. Allow the countertops to dry. Once they are dried, pry the concrete tops from the board molds, and lay them over the Formica. Screw, or use construction adhesive, over the edges of the Formica countertops.

Step 5 - Install the Concrete

Set the concrete in place, and then add a deep-penetrating concrete seal. These can be found at good masonry stores, home improvement stores, or from professional suppliers. This sealant is necessary to prevent water and moisture from penetrating the concrete.

Here are some tips for maintaining or improving your concrete countertop, once it's been sealed:

  • You can add features such as tile backsplash placements.
  • For a high shine on the concrete, use car wax. You can repeat the waxing once every six months or so.
  • Check the Formica regularly for cracking or splitting. If these signs occur, you will need to remove the concrete countertops, get rid of the Formica, and replace with other countertops.
  • Make sure that the gaps between the countertops are cleaned regularly, to avoid dirt and dust build-up.
  • You can also use polish on the concrete to get a good shine and clean the tops.