How to Remove Cement from a Car

Co-authored by wikiHow Staff

Last Updated: May 1, 2021

Concrete and cement splatters from construction sites and highway projects may seem a bit tricky to remove from your car without scratching the paint. However, you can easily remove cement stains on your own without breaking the bank! Start by dissolving the concrete with either a pre-made or homemade solution, then wipe off the remaining cement with a cloth and clay bar, and finish the job by adding a layer of wax.

Part 1

Part 1 of 2:

Dissolving the Cement Stains

1
Block off the area surrounding the stain with masking tape. Put down 3-4 pieces of masking tape (also known as painter's tape) on each side of the stain to give yourself a safety net for any overspray. If you spray the unblemished parts of your car with the cleaning solution, you could accidentally damage the paintwork.
- Do not use duct tape for this step because it can damage the car’s paint.
- If there are multiple cement stains, tape around each of them before moving on to the next step.
2
Use a special cement dissolver on the stains for an easy solution. You can pick up one of these dissolvers at a local hardware store or purchase a bottle online. The solution dissolves calcium from the cement, which means the leftover stains can be safely removed. These solutions are environmentally safe acid alternatives with an active ingredient that occurs naturally in sugar cane syrup.^{[1]
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3
Spray the stains with vinegar for a more affordable solution. Fill a spray bottle with half pure white vinegar, then top it off with lukewarm water. Shake the contents of the spray bottle for 5 minutes to mix the water and vinegar thoroughly. The vinegar’s acidity dissolves the cement, making it easier to remove.^{[2]
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- While a bottle of cement dissolver can cost more than $20, you can get a jug of vinegar for less than $10.
Variation: If there's any cement on your windows or windshield, use this vinegar solution to remove them. Spritz it on, wait 15 minutes, then wipe away the cement with a damp sponge.
4
Spritz the solution directly onto the cement stains to loosen them up. Saturate all the cement with your vinegar and water or commercial solution. Let the liquid soak in for a minute, then spray the stain again to further loosen up the cement.
- Don’t be afraid to soak the affected area with a ton of solution.^{[3]
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Part 2

Part 2 of 2:

Wiping the Cement Stains off the Car

1
Scrape away the cement with a kitchen spatula covered in cloth. Use a plastic or wooden spatula, not a metal one. Gently peel and scrape the cement from underneath to remove any loose concrete from the car. Dig the spatula underneath the cement stains and wiggle the spatula until the concrete loosens up and falls off.^{[4]
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- You have to cover the spatula with a cloth because it could damage the paint if it rubs up against the car by itself.
2
Press the cloth against the cement stains after spraying more solution. Once you’ve removed the big pieces of cement from your car, it’s time to lift thin layers of cement bit by bit. Apply a few sprays of your cleaning solution and push the cloth against the cement stain. Hold the cloth against the stains for a few minutes to dissolve the remaining cement.
- Repeat the process of spraying and pressing until you’ve gotten rid of most or all of the cement stain.
- Do not rub the cloth against the cement stain, as this could damage the paintwork and make the stain nearly impossible to remove.
Tip: Have a pile of cloths ready. You want to use a different cloth every time you press against the cement stain. This way, you’ll have a better chance of eliminating the entire stain.
3
Remove the last few grains of cement with a clay bar. Wet the stained area with a small amount of water or the included lubricant before you use the clay bar. Apply the putty-like material to the paint with a gentle, circular motion to lift off fine particles of debris.^{[5]
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- You can find a clay bar at your local auto shop, hardware store, or home improvement store.
4
Wax the area once it's completely clean. Put a thumb-sized glob of wax on a lint-free cloth and rub the wax into the paint with small, circular motions. Use horizontal or vertical rows of circles to cover the entire surface of the car, making sure to only apply an even, thin layer. Then, buff the wax off using circular motions.^{[6]
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- Car wax is available online or at your local auto shop.
- Only apply car wax once you’re sure it’s dry and every bit of cement has been removed from your car.