Exposed aggregate concrete
can give your home that natural classic feel which will give your overall property a warm ambience.
Let's look deeper
How is exposed aggregate done?
After the ground base preparation with reinforcing steel (rebar or mesh) and forming materials are in place, the concrete is placed, screeded, floated and troweled just like a normal smooth finish concrete job.
Then we must actually expose the surface of the concrete to reveal the stones.
This is done by spraying a coating of concrete "retarder"
to the surface of the concrete. This retarder is a liquid mixture which will prevent the very top surface (1/8 inch) layer of concrete to harden, as the concrete underneath hardens as it normally should.
With years of expertise we determine when it is the right time to wash off the top layer. What we look for is firmness in the concrete but not absolute solidity. When the time is right, we then take a regular garden hose or light duty pressure washer and gently wash off the top layer of concrete to expose the beautiful colored stones on the surface.
After allowing the concrete to fully cure for 28 days, it is then time to acid wash and seal the aggregate. Acid washing is done carefully with a general mixture of 7 parts water to 1 part muriatic acid. The acid eats away at any concrete residue/film on the exposed stones and polishes the aggregate.
Next, after allowing the concrete surface to thoroughly dry, a thick coating of concrete sealer is applied to the surface which is the final step to making the exposed stones glisten and to have the perpetual "wet look"
Are there different types of exposed aggregate?
Often 10mil rock and pea gravel is used for the concrete mix, but by far the most beautiful finish is with a mixture of Chilliwack Rock
, as it has a multitude of colors and shapes.
Exposed aggregate quick fact
A substitute for using concrete retarder, which slows down the curing of the concrete surface, is to use sugar mixed with liquid. In fact, the old school concrete placers would often use Coca-Cola and Brown Sugar, as a substitute. And it actually works!
Some Samples of our Exposed Aggregate Concrete Work
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