DIY Exposed Aggregate Driveways
Installing an exposed aggregate driveways is one of the easiest ways to get a decorative driveway. Exposed aggregate driveways can look great and will last a very long time. So how do you do it yourself and get a great result?
How to Install a Exposed Aggregate Driveway
An exposed aggregate concrete driveway
- Excavate and install your form work
- Select your concrete mix
- Pour and finish your driveway
- Expose the aggregate
- Coat your driveway
Excavate and install your form work
This is the same as any method or driveway finish whether it is stencil, stamped or plain concrete. Your form work will hold the wet concrete in the right shape until it sets. Most concrete form work is made from timber and timber pegs are used to hold it in place. You also set the level of the concrete by leveling the form work to the desired correct height.
Tip: make sure you have the form work ready before to order your concrete mix.
Select your concrete mix
This is where exposed aggregate concrete is different from normal concrete. Normal concrete uses blue metal or plain stones as the aggregate in concrete and it doesn’t really matter because it is being colored or colored and stamped so the aggregate is not going to be seen. Exposed aggregate concrete uses the aggregate as a feature so you can order your concrete with decorative stones in it. The other way to do this is to order normal concrete mix and then board cast decorative over the top evenly and trowel in. Your concrete mix can be order with plain or colored concrete with decorative stone in so when your aggregate is exposed you will see all the colorful stones set in plain or coloured concrete.
Tip: for the bit of bling – throw some colored glass pebbles across the top and trowel as these add a bit of sparkle.
Pour and finish your driveway
Pouring your concrete into the driveway form work is simple however you should, where possible, have access for the concrete truck to back up and pour directly into the form work area. This is the best way because you just spread it out and level it off. However sometimes full access is not possible so a concrete pump will be required or for small areas you can wheelbarrow it in. To hire a concrete pump truck you must book them it for the day you want them and order your concrete mix for the same time. If it is raining on the day or looks like rain you can just ring them and postpone the concrete and pump truck.
Expose The Aggregate
Exposed Aggregate
There are two ways expose the aggregate and both involve removing the top 1/8 of an inch, or 3mm approximately, of the top layer of cement paste and so exposing the aggregate. The first is once the concrete has been troweled smooth you lightly spray top of the concrete removing the top of the cement paste and exposing the aggregate. This technique is best suited to small areas and the danger is that too much paste will be washed away and result in unevenly exposed aggregate. The second and best way is to use a cement retarder to stop the top layer of cement paste from setting. The concrete is toweled off smooth and then using a pump up sprayer, spray on the cement retarder evenly across the surface. The next day the concrete will be set and you use a pressure sprayer to remove the top layer of cement paste because this has been retarded from going off. This ensures an even exposure of the aggregate which is important across a wide area that is highly visible.
Tip: You can buy cement retarder at concrete product suppliers that supply stamped, colored, and steciled concrete products.
Coat the driveway
You must let the concrete set for a minimum of 14 days before coating it with a clear sealer. Also you must not drive on it for 28 days so it has reached full strength. Coating your driveway with a clear sealer does two main things. One it protects the cement from dusting and the second is a clear sealer brings out the colors in the decorative stones. While water based sealers are available the best and most durable I have seen are the two part sealers as they leave a nice hard coating on the driveway.
Installing a driveway in exposed aggregate can be done by most people and with a bit of care you can get a great result and save yourself alot of money. Why not give it a go?
