Concrete is a remarkable building material, and because of it’s compressive strength, it is great for things that will carry weight, like foundations, retaining walls and driveways. However, concrete is also somewhat porous, and the top layer in particular often absorbs everything it comes into contact with.
That means that sooner or later, you’re going to be asking about the best way to clean a concrete driveway. Here’s what you need to know.
Concrete vs. Cement
Often, people who don’t work with concrete will try to find pages like this using a search like “how to clean cement driveways.” However, that’s not really that accurate. That’s because cement is a component of concrete, but it’s not the same thing as concrete.
To make concrete, you have to mix sand, stone, cement and water in the right proportions. This creates a chemical reaction, which lets the concrete get as hard as, well, concrete.
So if you’re not having any luck finding out how to clean cement driveways, that might be why!
Check the Weather!
Before you start preparing to clean your concrete driveway, be sure to check the weather.
You don’t want to do this kind of job on a day that is too hot and sunny, because you’ll get very hot (and possibly sun burned) spending time on your driveway in the heat.
You also don’t want to do this when it’s going to rain, because your cleaning products might be washed away before they can get the job done.
The best time of year for cleaning a concrete driveway is usually in the spring time. All the moisture from the winter is gone, but the weather is not so hot yet that being outdoors for a couple of hours is unbearable. Nevertheless, a deck chair under an umbrella, with a few cool drinks nearby is a great place to wait for your cleaning products to do their job!
Concrete Driveway Cleaning Tools
Now that we’ve got the technicalities of concrete versus cement out of the way, the next thing we should address is what kind of tools you will need to clean a concrete driveway.
This depends a lot on how badly stained your driveway is, and what kind of substances it’s stained with, but a concrete driveway cleaning kit will probably include the following:
- A stiff bristled broom and scrubbing brush
- A pressure washer or hose
- A bucket
- Various nozzles for your hose or pressure washer
- Spill absorber
- Paint stripper (if you have paint on your driveway)
- Concrete cleaner (a commercial concrete and driveway cleaning solution)
- Concrete sealer
Now that you know what you will need, it’s time to get down to the details of how to clean a concrete driveway.
Concrete Driveway Cleaning Methods
It’s time to get to the various methods of cleaning a concrete driveway. Before we do, it’s important to mention that you should always follow all manufacturer’s instructions for equipment and chemicals. It’s also a good idea to wear eye protection and rubber gloves, if that is recommended by the manufacturers.
Even if they don’t expressly recommend this, you might want to wear these kinds of safety gear while you’re cleaning your driveway, because water, dirt and debris can easily get into your eyes, and there’s no telling what kind of allergic reactions you could have done this kind of work.
Now, let’s take a closer look at how to clean various substances off your concrete driveway.
Paint is actually quite a common thing to have on your concrete driveway. If you don’t have a drop sheet down while you’re painting, it’s very easy to splash some on the concrete.
The good news is that paint stripper will usually take it off.
Apply the paint stripper to the paint on the driveway – and be careful! It’s very caustic!
Leave the chemical to soak in for the recommended time, and then use a scraper to remove it and the paint below. You may need to do this more than once if you have a large stain or it’s particularly stubborn.
Then scrub the area with a brush and rinse with water.
Oil and Grease
Oil and grease from cars are another common stain on concrete. In this case, the treatment depends on how long the oil has been on the concrete.
If it’s a fresh stain, use a spill absorber on the stain, and follow the manufacturer’s instructions. Leave it to do its job and then sweep and scoop it up.
Next, on fresh and set in stains, apply degreaser according to the manufacturer’s instructions and leave to sit for a few minutes. Scrub the area off and rinse.
You can also try applying dish soap to the area if there is still some greasy residue left behind. It doesn’t only remove grease from your dishes!
Rust and Dirt
When you have rust and dirt on a concrete driveway, the best product is usually a commercial concrete cleaner that is made for that type of stain. Follow the instructions about dilution and application, and then let it sit for a few minutes.
Rinse and scrub the area of the stain to remove the last of the rust and dirt.
Algae and Moss
Many driveways develop dark greenish stains in areas where there’s a lot of water. Removing these stains is usually fairly easy but requires some elbow grease.
Scrape the moss or algae off the area and then use a commercial product formulated for removing algae. Follow the instructions and let it sit, and then rinse and scrub to remove remaining stains.
Once your driveway has been spot cleaned in areas where there are stains, using one of the suggestions for how to clean a concrete driveway above, it’s time to get out the pressure washer or hose.
Make sure you use the right kind of nozzle for the type of dirt you’re dealing with, and if you’re using a hose, make sure the water pressure is sufficient. You can also use a stiff bristled outdoor broom while hosing to help remove the dirt from the surface.
Start at the top of the driveway, so dirty water won’t run over or pool on clean areas and be sure to wear eye protection and any other safety gear that might be appropriate for cleaning products you have used. Here are the steps for washing your driveway properly:
- Wet the whole driveway using your hose
- Apply concrete cleaner to the driveway surface – you can also add this to the cleaner tank on the pressure washer
- Rinse the concrete to remove the concrete cleaner, using the pressure washer
- Make sure you have removed all the concrete cleaner and any remaining residue from other cleaning products you have used
- Allow the driveway to dry
Once your driveway has dried, you might find that you can still see some faint remains of the stains you’ve been trying to remove. If this is the case, you can try the same processes again to remove the remaining discoloration. However, you should know that if you have very old, soaked in stains on your concrete driveway, you might not be able to remove them completely.
Repair Your Driveway
Now that your driveway is clean, and you’ve found the best way to clean concrete driveways that are stained and dirtied with the things yours was, it’s time for some repairs and maintenance.
In order to keep your driveway clean, you will want to seal it, but before you do that, you need to repair any cracks and other damage to the surface.
Apply weed killer to any plants that are growing through cracks in the concrete. If they’re allowed to keep growing, they will eventually start to damage the concrete around them.
Use concrete crack filler (which you can buy from a hardware store) to fill any small cracks. This is available in tube form, but there are also putty style products that you can apply with a knife or scraper.
If you have large cracks or holes in your concrete, remove the broken pieces and clean the area. Then apply concrete bonding agent to the broken edges and fill the hole with ready mixed concrete. You can buy this in bags from hardware stores too, and you simply mix it with the right ratio of water.
Smooth the top of your repaired area down and allow the repair to set completely.
Once your newly clean driveway is completely dry, and any repairs you have made are fully set, the next step you want to take is sealing the concrete. This will prevent future stains and ensure that you never have to wonder how to clean a concrete driveway again!
First, visit your hardware store to find an appropriate concrete sealant. There are several types on the market, so speak to the people who work there to find the best one for your needs.
Make sure you have enough concrete sealer for your job. There is usually a coverage rate on every product, so you can use the square footage to calculate how much you will need. Don’t forget that you will do two coats though – so you need to double the square footage you need to cover.
Once you are ready to get started, read the instructions carefully, and then use a garden sprayer or a roller with a long handle to apply the product evenly to the surface of the concrete. Make sure the layer is thin and even and remember not to paint yourself into a corner!
Allow the sealant to dry completely, and then apply another thin, even coat to your concrete.
Once your concrete is sealed, it will be protected from most types of stains, so cleaning your driveway will be a simple matter of hosing it off.
General Tips and Advice
If your concrete driveway is very damaged or is sagging in places, you might need more than information about how to clean a concrete driveway. If you’re in doubt about whether it can be salvaged, ask a paving company to take a look. They’ll be able to tell you if you can save your driveway or you need to replace it, and how much the replacement will cost.
If you haven’t sealed your driveway yet and you have a spill onto your concrete driveway, be sure to clean it up as soon as possible. The longer stains sit on concrete, the longer they will sink in and the harder it will be to remove them completely.
If you have stains that won’t budge completely no matter what you do, consider staining your concrete driveway a darker color. There are concrete stain products that are also sealers, and a darker shade will look good and camouflage any remaining stains.
Not Usually Difficult, But Quite Time Consuming
As you can probably see from these tips and instructions, the process of cleaning concrete driveways is not particularly difficult, if you have the right equipment and cleaning products. But it can be time consuming, particularly if you have a lot of stains and damage.
If reading these instructions about how to clean a concrete driveway makes you think you might not hate those stains so much after all, then you might want to consider another option.
There are professional companies that specialize in cleaning concrete driveways and walkways. They know the best ways to clean concrete driveways, and their rates are often very affordable. It might be a good idea to get a quote to have one of them clean your driveway.
You can always opt to do the sealing yourself at a later stage, or the company might be able to offer you this option as a separate quote. It’s certainly a lot easier to clean a concrete driveway this way!
Sometimes, it’s not possible to remove every stain completely from a concrete driveway. But a good cleaning can certainly make it look almost as good as new.