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Popular Techniques for Revealing the Exposed Aggregate in Your Concrete Flooring

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If you want to give your concrete floors a nice decorative finishing touch, removing the top later of the concrete surface to expose the sand and gravel part (aggregate) is an option you should consider. Exposed aggregate is a common feature in homes with concrete floors because it offers a long-lasting and visually appealing look. There are various ways of exposing the aggregate on concrete surfaces. Here is a look at some popular installation techniques you might want to use for your installation. 

Water washing

Also commonly referred to as the 'water wash off technique', this method involves brushing and washing the concrete surface with water once the poured concrete has hardened. Where high pressure washing equipment is used, this method is known as water blasting. Water blasting requires the use of large volumes of water, and it is therefore common to encounter run-off issues. Because the high pressure of water sprayed on the surface of the concrete can send debris flying in all directions, operators must put on face shields, protective clothing and rubber boots to avoid getting injured. For smaller jobs, where the use of special tools may not be necessary, scrubbing with water and a hard brush may achieve the desired results. This method may be old, but it remains quite effective.


Other people know this technique as abrasive blasting. It involves revealing the aggregates within stiffened concrete by blasting the surface layer with sand. Sandblast finishes may contrast from light to medium to heavy, depending on the amount of aggregate present when concrete is exposed. The simplest form of decorative sandblasting involves eroding a very small part of the top layer surface so as to change its colour. But in most cases, sandblasting is used to define borders and achieve different textures and colour palettes. Initially, it is the surface colour of the cement that will dominate, but as more of the top layer gets eroded away, the natural colour of sand and gravel will begin to gradually show. The timing of the sandblasting is based upon the stiffness of the aggregate, scheduling and the aesthetic appeal desired, among other factors that affect the quality of the installation.

The best way to ensure you choose the right technique for your exposed aggregate concrete flooring finishing project and achieve the desired results is to consult a concrete contractor. These contractors can not only offer you with advice on what method of application you should use, but also perform the project on your behalf.