Exposed Aggregate Concrete Explained

If you're thinking of creating a decorative space in your backyard or driveway, then exposed aggregate concrete should be your first choice. The concrete is achieved when you remove fine aggregate and the top layer of cement from fresh concrete. This leaves you with aggregate particles (crushed stone and gravel) on top.

Many homeowners prefer it for their pool decks, paths and driveways because it's skid-resistant and durable. Read on to learn more about this type of concrete.

Laying Exposed Aggregate

Exposed aggregate comprises of pebbles, stone, water and sand. These items are mixed in different proportions depending on the client needs to achieve different finishes. For instance, to achieve a topping aggregate, you have to lay an aggregate finish as a topping once you've laid the sand and cement base.

Standard Aggregate

The standard aggregate is one of the most common and easiest finishes to prepare. While the preparation may be straightforward, you need the help of a professional contractor to help balance and measure the materials to achieve the desired balance.

Preparing Standard Aggregate

When preparing a standard aggregate, a mixture of gravel, sand and concrete is mixed to the desired ratio before being poured to the surface you wish to work on. The surface should then be levelled to get rid of any inclines or excess materials.

Once this is done, bull float or magnesium float is added to remove exposed edges as well as any imperfections. Many concrete contractors will let the mixture rest for a few hours before spraying a surface retarder.

This helps the underlying concrete dry and harden faster while the top remains wet and removable. The last step is to hose off the surface which exposes the internal aggregate, helping it achieve an exposed surface.

Seeded Aggregate

This type of finish is different from other ways of laying concrete due to the steps followed in adding the finish. In seeded aggregate, the concrete mix is poured on already prepared wet sand and cement base. While this may seem easy and straightforward, it is a complex procedure that requires careful expertise and preparation. If not done properly, you may end up with an uneven finish.

That said, when preparing the concrete, make sure that your choice of aggregate matches with the texture that fits the surface. For instance, if you're making an aggregate for patios and poolsides, it should be of fine texture so that people don't feel any discomfort when walking barefoot

Contact a concreting service for more information.

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