How to throw a concrete countertop

Concrete countertops look great and last for years – and they’re not hard to make yourself!

Making concrete countertops isn’t difficult Just follow these instructions and you’ll have strong, beautiful countertops made with your own two hands.

For this job, we will use 1.2 m concrete lintels. (Depending on your layout, the exact materials and tools might change.) Start by building block columns that are 1.2 m apart from the outside edge. This will mean that the lintels will rest on them and cover them. Once the columns are built, rest the lintels on them, making sure they lie snugly together.

Make a box of plywood around the lintels, screwing the plywood together and attaching it to the lintels with nail-in anchors. Make the box slightly bigger and deeper than the lintels, so that the concrete hides the edges of the lintels. Also, make sure that all the timber is level now – it’s your last chance to do so!

Mix the concrete, using a ratio of one part cement to three parts sand and two parts stone. Add enough water to make a mix that is not too watery. We also recommend adding keycoat to the mix to make it extra water resistant.

Pour the concrete into the box and make sure the concrete gets into all the corners, then gently knock the sides with a hammer to remove bubbles. Use a straight edge over the surface to get a smooth finish and make sure that it is level.

Once the concrete has just started to harden, give it a gentle float to remove any high spots. Cover the concrete with plastic and spray it with a little water every few days to slow down the drying process and reduce cracking.

Leave the concrete for at least a week and then remove the wooden box. Once the box is removed, seal the concrete with something like Woodoc 45, a sealant that penetrates tiles and cements and which will protect the countertop against stains and oils. It dries to a clear finish and application is easy – simply paint it on using a block brush.

There you have it – beautiful concrete countertops made by you and which will last for many years of entertaining. Builders has everything you need for this project and any other DIY project around the house, both instore and online at builders.co.za.