Exposed aggregate concrete is a very popular choice amongst homeowners who wish to refinish their driveways. In addition to being aesthetically appealing, this material is also weed resistant and durable enough to withstand severe weather conditions and heavy traffic. However, whilst it is certainly one of the more low-maintenance materials, it does still require some upkeep. If you intend to use this material for your new driveway, here are three things you'll need to do to keep it in the best possible condition.
Wash it regularly
The slightly textured nature of exposed aggregate makes it more prone than smoother-finish driveways to dirt accumulation. As such, it's important to wash it on a regular basis. To do this, you'll need a stiff-bristled outdoor brush, a degreasing agent, a bucket of warm water and a hose. Allow the mixture of the degreaser and warm water to soak on the driveway for a few minutes, to loosen any oily stains and grime, before using the brush to remove any deeply-ingrained particles of soil. Then, hose down the entire area to rinse away both the cleaning solution and the dirt. It is not advisable to use a power washer for this task, as the pressure of the water could end up damaging the concrete.
Spot-clean rust stains
Whilst oil and water stains can usually be removed using the above-mentioned washing method, rust stains are a little trickier to deal with. If your exposed aggregate driveway happens to feature certain stone particles which contain iron oxide minerals, then you will most likely have to deal with this type of stain at some point. It tends to occur when the aforementioned minerals oxidise after being exposed to rainwater and air. The most effective product with which to remove this kind of stain is hydrochloric acid (sometimes known as muriatic acid). However, this is a highly potent chemical and great care should be taken when using it.
Whilst using pure hydrochloric acid will remove rust stains, it could also alter the colour of the concrete and leave you with a patchy, unsightly looking driveway. As such, you should only ever use a diluted solution of this chemical. It's also important to employ certain safety precautions before applying this acid; you should cover up any exposed skin with protective clothing, such as rubber boots and gloves, and wear goggles to shield your eyes from any acid splashes.
Apply a sealant
Using a sealant on your exposed aggregate driveway is an excellent way to protect it from further stains as well as damage caused by fluctuating temperatures and exposure to moisture. When choosing a sealant, make sure that it is UV resistant and that it is designed to repel most types of staining, including both water and oil marks.