Exposed aggregate concrete refers to a mixture of gravel, pebbles, and even soft and buffed glass that is put on the top layer of concrete. This aggregate provides a textured surface that makes it safer for walking and driving and also improves the overall look of the concrete. You can usually choose to have exposed aggregate concrete poured on your property, for the driveway, patio, or walkways. Note a few questions you might have about this process, and then discuss your options with a contractor as needed.
Does the aggregate come loose?
If you've ever seen a concrete surface with pits and holes where aggregate has come loose, note that this is probably very old concrete that is likely to break down and crack, aggregate or not. Additionally, allowing water to build up on the concrete without proper drainage might cause the aggregate to come loose. Your installer will tell you the best way to maintain your concrete and keep the aggregate in good condition, but note that exposed aggregate usually lasts for years, if not decades, under standard residential use.
Can a homeowner install exposed aggregate themselves?
Note that installing concrete with exposed aggregate is not a matter of just shaking a layer of pebbles or other materials over fresh concrete; you need to ensure it's not so bumpy that it causes a tripping hazard, and you need to work quickly so you add the aggregate before the concrete sets. You also don't want the aggregate material to get spread around the job site and create a mess. For these reasons, it's usually best to have a professional manage this installation for you.
Can exposed aggregate be applied over existing concrete?
If you don't need an entirely new driveway or patio installed, you can usually have a new layer of concrete applied and then aggregate added to this top layer. It may require some grinding of the existing concrete so it provides a bumpy surface to which the new layer will adhere, and you may be limited as to the aggregate choices so that they adhere to a top layer of concrete. However, this can usually be done by an experienced installer who can work with you to choose an aggregate you prefer. They can also note how much prep work needs to be done to add that top layer of fresh concrete over the concrete you already have on your property.