How To Construct And Install Concrete Countertops How To Construct And Install Concrete Countertops

Concrete countertops are popular because of their versatility. They can be made to look like wood, clay and even natural stone. Concrete is also popular because it’s cheap to work with. While installation can be messy, the results will be worth it. Here’s how you can do your own.

Step 1

Use melamine wood to start building a form. You will want to choose a plastic finish because it will make the concrete dry more slowly. The slower the concrete dries, the stronger it is. Using a plastic finish will also prevent the concrete from sticking to the sides.

You can build this by simply attaching the sides to the bottom with a staple gun. You don’t want to drill the slab after it’s been built, so create your voids prior to this. It’s also important not to use particle board as this will absorb water.

Step 2

Fortify the slab with polypropylene fibers and reinforcing rods using a diamond lath. This will keep the countertop strong.

Cut the diamond lath 1 inch shorter than the edge of the form. You can use rebar around the sink cutout if you need it. Make sure all your measuring and cutting is done before you prepare the concrete mix.

Step 3

Mix the concrete according to the manufacturer's directions. The better you mix the concrete, the more durable your countertop will be. Use a mason’s hoe to blend all dry ingredients well. Carefully measure any liquid you are using and slowly mix them together. Once mixed, the concrete will be ready to immediately  pour.

If you pour it in layers, it will minimize the time between each step. Don’t worry if you see cracks forming as the concrete dries. The diamond lath and poly fibers will keep the cracks tight and microscopic.

Step 4

Start by packing a 1-inch strip along the edges with concrete. Then fill the middle with the concrete once it’s been reinforced. Add rods and diamond lath again, and then add a layer of regular concrete.

You want the concrete to look like one seamless block, so make sure you are measuring all the ingredients. Guessing can cause variation in consistency and color which won't look good on your countertop.

Step 5

This concrete will be firmer than the type of concrete used in other applications. You will need to press it pretty hard into the form to compact it well. This will be serious manual labor, so be prepared.

Add more concrete to fill any low spots, and then smooth it out. Pack it again and check for more low spots. Continue this process until the form is packed well and the concrete is smooth.

Step 6

Allow at least 2 hours for the concrete to begin to set. At this point, you can use your trowel on the surface. If you overwork the concrete, aggregate will pop up and be hard to smooth out.

If you see water puddles starting to form, leave the concrete for another half-hour before you  come back and try again. In really hot conditions, you will want to cover the form with a wet burlap bag to slow down the process.

Step 7

You can remove the forms after 2 days. Use a flat pry bar to separate the forms at the joints.

Step 8

Wear a mask while you can sand down any sharp edges. Etch the surface with a muriatic acid, and then rinse it completely.

Step 9

Prepare a latex additive and apply it to the surface with a rubber grout float. This will fill any voids that have been created. Let this cure for at least 3 weeks.

After the counter has cured, grab a few friends to help you begin installing the countertop.

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