How to remove paint from concrete? – with or without chemicals

Saad Iqbal | 🗓️Modified: December 26, 2021 | ⏳Time to read:12 min

A lot of homeowners are finding ways to remove paint spills from concrete with or without chemicals, after a major home renovation project. They try to use vinegar or scratch dried paint off the concrete but can’t get results. That’s because they’re not following the correct way or technique to get paint off concrete.

No matter the paint is new or old, removing paint from concrete is not an easy task.

But don’t worry! It’s quite achievable, if you use right kind of tool set and correct method. Whether it’s a thick coat you intentionally made or just a small accidental spill, it takes time and effort.

It’s not like you can use any method for every type of paint. The method that works well against matte based paint may not work against an oil-based paint.

Same stands true for the type of surface or structure. You may use chemicals on the concrete stairs but you might be looking for a method to remove paint without chemicals in order to get rid of paint spills in kitchen or basement walls.

So, here’s our take on how to remove paint from concrete with easy yet effective techniques.

How to remove paint from concrete?
How to remove paint from concrete?

Removing Paint from Concrete

Home renovations projects are tricky and overwhelming. In your excitement you might forget about the mess you’re going to deal with at the finishing stages of the project. For example if you’re taking plunge of paint finishing your basement, you have to deal with spills at the end That’s because at times you can’t avoid kinds of paint spills on concrete surfaces like floors. Later on, these spills can spoil your grand party.

Also Read: Difference between Cement and Concrete or Mortar

Using Chemicals

First, use chemical paint strippers to clean the required area. Use the right solution of paint stripping chemical. Then use a soft brush or rag to remove the excess paint. Lastly, rinse off the area with hot water.

Removing paint using paint stripper
Removing paint using paint stripper

Removing paint from concrete without chemicals

You not always have to use toxic chemicals for cleaning paint off concrete. Your kids can come in contact with such toxic chemicals. Also, remember that if you are going to use these chemical strippers to clean up old paint stains on your garage floor, you need to make sure that you wear protective gear so that you will not be accidentally doused with the chemicals.

Using Bristol brush and nail polish remover

Sometimes your kids come out and absolutely destroy your backyard concrete floor with tattoos and acrylic paint from their rock painting. For such, you can use a simple metal bristle brush. You can buy one from the nearby hardware store for over $1. But it is so awesome in removing paint and stains.

After cleaning you can use some water to rinse the surface. You can also use this process to remove spray paint. If you find it a little tough, you can pour a bit of 100% acetone on and then scrub it. You can also remove the paints and spots using nail polish remover.

Removing paint from concrete without chemicals
Removing paint from concrete without chemicals

Cleaning using detergents

Powder washing is also a popular way of removing paint from concrete without chemicals. The area to be clean of paint must be thoroughly cleaned using mild detergents and water. Mix non-metallic powders into the water to form a thin paste. Apply the paste onto the affected area and allow it to set for some time. But this method only works if you’re only looking to remove paint splashes during your recent renovation project. That’s because if the paint finds time setting in the porous concrete, mere washing with powder might not be enough.

Also Read: What is concrete grinding? How to do it? 

Using detergent
Using detergent

Using pressure washer

Pressured water can also be used to remove paint from concrete without chemicals. At high pressure levels, it can easily clean off layer of paint, dust, grease, and other dirt from concrete surface. Before using a pressure washer, you may want to apply the paint stripper and clean the surface with detergent and water. With such, use the pressure washer in circular movements to completely remove the paint from the concrete surface.

If you want to clean the stains from your walls, first find out the direction of the stain and use the Paint Stains Remover. Apply the Paint Stains Remover on the stained area and scrub it carefully using a soft brush. Rinse it off after several minutes to remove the stubborn stains.

This step may require you to use more than just a good supply of rinsing solutions. Some kind of absorbent product should work well for these kinds of stains. If you cannot find any at home, you should consider buying a good variety of non-toxic paint strippers.

After you’ve applied paint stripper or detergent to the paint spots, clean off the paint using the pressure washer. With pressure washer at 3000 PSI, it can blast away the paint stripper residue and the layer of old paint. Make sure you hold the washer’s wand firmly and keep it at a distance of 12 to 18 inches from the concrete surface. If your concrete area is large, you might have to focus on small chunks to make it manageable.

Using pressure washer
Using pressure washer

So, why pressure washing is a preferred solution?

Well, manual scrubbing and scraping paint off concrete walls could be a time consuming and a labor-intensive method. Even if you use scraper or a grinder, the methods would be ineffective without pressure washer. So, no matter what other methods your use for removing paint of concrete garage or driveways, make sure you give finish with a pressure washer. I’d recommend never scrubbing or scraping paint in dry state because this would release paint dust and fine particles that could end up in your eyes or may get into your lungs, if you’d breathe them in.

Similarly, chemical stripper may help you in removing paint from concrete with less effort but it can also increase the risk to your health and to the environment. Similarly, some chemical strippers require a setting time of six to eight hours; so it is crucial if you need to finish the concrete again with new layer of paint.

Using an angle grinder

Using an angle grinder is a lot more efficient and doesn’t cost near as much as any kind of other chemical treatments or power washing that most people recommend to get paid off concrete. Moreover, the whole process only took about 30 minutes.

You can use an angle grinder having a four inch diamond cup wheel. You can get such a grinder cup at any hardware store for 50 to 60 bucks. They come with multiple rows of teeth and different grits. So, you need to find one that is going to work best for project keeping in view the type of paint and concrete finish.

With this method, you can even clean concrete surface with multiple layer of primer and paint, even if it’s been over past 20 years.

Using grinder
Using grinder

I recommend you wearing some sort of respirator and safety glasses during this process just because it does get pretty dusty. Moreover, the wheel does leave a couple scratches and grooves that aren’t too noticeable to touch but you can visually see them.

Anyhow, if you’re repainting the concrete, I don’t think it’s an issue to just leave it and paint over i

t. If you’re not, I do recommend that you use a little bit of acid treatment to go ahead and just flatten that paint marks out.

But after that process, it’s just rinsing it all off and repairing any cracks or grooves before you repaint it.

Also Read: Concrete Definition – 3 Basic Components – Grades

Soda Blasting

If you’re having a paint issue on a bit delicate concrete surface and a large area is already affected, soda blasting is the way to go. It is a relatively newer technique to strip paint off concrete walls and garage floors. The method is effective, environmentally friendly and will not damage your concrete surface.

All you need is a soda blaster and sodium bicarbonate (baking soda). Soda blaster is portable pneumatic equipment that is effective in cleaning paint or spots from concrete surface. The particles of sodium bicarbonate are blasted against a concrete surface using compressed air. Due to this, it has a much milder abrasive effect than sandblasting. Soda blasting can also be used to remove graffiti from the walls or floor. (So, if you’ve kids with painting skills – this might be a handy tool to have in your home).

Soda Blasting
Soda Blasting

Do you know?  Soda blasting was used to restore and conserve Statue of Liberty in the 1980s.

Sandblasting

Unlike soda blasting, sand blasting is more rigorous and when handled incorrectly can damage your concrete surface. You need to work slowly and cautiously to get best results.

If you have a concrete driveway that is – let’s say around 200 mm deep, you can restore the shine and remove paint spots off using sandblasting. There’s no involvement of harsh acids and does not give off fumes. So, it’s an environmentally-friendly and effective way to remove paint off concrete. Sandblasting also known as grit blasting involves forcibly propelling an abrasive material against a surface.

Also Read: Does heat kill mold in house? Get rid of the mold with heat

Using Sand blasting
Using Sand blasting

How to get rid of Spray paint from concrete?

As spray-paint has deep roots in the porous concrete surface, I’d recommend using a mixture of tri-sodium phosphate and water. It’s a chemical compound that’s famous for removing grease and stains from concrete and other common surfaces in your home.  All you have to do is to dilute sodium-phosphate in water and apply the mixture to the affected area. Let the mixture sit over some time and then scrub it using simple brush or Bristol brush. That’s set; you have easily removed the spray paint off concrete.

Removing Latex paint from concrete surface

Latex is a water-based paint that is similar to acrylic paint but is made with acrylic resin. Being water-mixed, latex paint spills are much easier to remove from concrete surface. You might find it strange, but a lot of people use alcohol to remove latex paint from concrete surfaces. So, just apply a generous amount of alcohol to the affected area and rub it a rag. This will loosen the paint helping you to remove.

If the paint spills are dried and stubborn; you might have to us paint thinner. It is a stronger solvent; you can purchase it for dedicated water-based paints.

Anyhow, I’ve been using ammonia to clear off the latex-based paint spills off my concrete driveway. I mostly use a cloth saturated with ammonia to get best results. You can apply a generous layer of ammonia to the affected area and let it sit for an hour. Ammonia will cause the paint to bubble off that you can easily scrub off using brush.

Also read: How to get rid of wood mites? 

Removing oil-based paint from concrete surface?

Oil-based paints are stubborn and difficult to remove. You can’t just use a paint scraper alone. Anyhow, we recommend using paint scraper to loosen the paint off. But at the end you must finish the job using a pressure washer.

Removing paint from concrete walls

You can also use heat gun to remove paint off concrete walls. Just clean the painted area and try to prepare the heat gun properly. Once it is hot and ready, apply it from a distance of 5 inches away from the surface. At the end you can scrape away the paint.

Also Read: What is a stem wall – meaning – detail – benefits – design – procedure

The bottom line

Looking to get rid of paint spills or paint spots off concrete wall or surface? Well, there’re many ingenious ways of removing paint. Some methods are based on chemicals while some methods are there to remove paint from concrete without chemicals. The water-based or latex paint are much easier to remove than oil-based paints. So, if you’re looking to remove oil-based based from basement walls you can use heat application. However, if you have paint spots on your driveway or garage you can use other methods that are not based on chemicals.

 

Saad Iqbal is a professional civil engineering and freelance write. He's passionate about structures, construction management, and home improvement topics. He's been working as a Senior Engineer in a consultant firm for over 8 years. Besides he loves writing informative and in-depth content focused on construction and home-related topics. You can catch him at his linkedin page or reach out via our contact us page.

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