Concrete is a popular building material thanks to its durability. It’s resistant to harsh weather, abrasion, and chemicals—as well as porous.
The small holes in concrete make it a highly absorbent material that readily absorbs liquids — including paint.
Thanks to concrete’s porosity, paint can seep millimeters below the surface, making it extremely difficult and time-consuming to remove.
To take paint off concrete, you will need to clean the surface thoroughly, wait for it to dry, scrape away the color, and finally apply and remove paint stripper — possibly multiple times.
This guide provides a step-by-step guide on how to remove paint from concrete.
Here are the steps to follow:
- Clean the Surface
- Scrape Away Paint
- Apply Paint Stripper
- Remove Paint Chips and Residue
- Repeat as Needed
Removing Paint from Concrete
#1. Clean the Surface
The first step is to give the concrete a deep cleaning. Getting rid of extra particles coating the surface is essential if you want to maximize the next step’s efficacy, applying paint stripper. Start with a dry clean. Use a broom and vacuum cleaner to remove debris, dust, and dirt.
If the concrete is muddy, use a high-pressure hose or power washer to eliminate any caked mud.
If this isn’t doing the trick, you can create a mix of soap and water. Ideally, add diluted trisodium phosphate, TSP, to help deteriorate the dirt.
If you use TSP, make sure to wear protective gloves. Otherwise, you risk damaging the skin on your hands.
Then, use a long-handled brush to work the liquid into the concrete. Longer bristles will penetrate the pores best.
Afterwards, rinse the area thoroughly to remove all soap residue and dirt. Finally, wait for the concrete to dry completely.
If the sun is shining, you may be able to wait several hours. If not, you may have to wait overnight for the surface of the concrete to dry out thoroughly.
#2. Scrape Away Paint
Before you move on with the next step, grab professional protective clothing. You want gloves and a ventilator mask. Inhaling paint particles may be hazardous for your health.
This is especially critical if you don’t know what type of paint you’re dealing with. Lead paint, in particular, is a health risk.
After washing, some of the paint may already have started to chip or wear away. Use a putty knife to peel and scrape the remaining residue off.
A putty knife is specially designed for eliminating paint without gauging the surface beneath. Once you’re done, you may want to dust and vacuum the surface again to eliminate debris.
Putty knives come in different sizes, from 3/4 to 6 inches. You can choose the size that best suits your surface area.
If you’re on a budget, a plastic-like polypropylene putty knife blade will be sufficient. If you need something more heavy-duty and have the funds, opt for a carbon steel blade, which is more durable.
#3. Apply Paint Stripper
Next up, apply a paint stripper. Again, wear gloves to protect your hands during this process. You should also wear a respirator to protect your lungs as well as long-sleeves in case of splashes. Protective eyewear — shatterproof plastic goggles — is essential. You can buy them at your local hardware store.
Make sure to use the appropriate product depending on the type of paint you’re dealing with (oil-based paint versus water-based paint).
If you don’t know what type of paint you’re trying to remove, check the product label. Just have a brand name? Email the company to ask. You should be able to find a customer service email address online.
If you still can’t figure out what type of paint you’re facing, opt for an oil-based paint thinner.
Apply a thick layer of the paint remover to the affected area. Let it sit for six to eight hours. You need to wait for the chemical reaction to take effect.
#4. Remove Paint Chips and Stripper Residue
After the requisite time window has passed, you can start removing the paint stripper residue and any loose paint chips or flakes. Again, wear a mask to protect your airways. You can use a paint scraper or a wire scrub brush to pry chips loose.
If you are working on a larger surface area, a pressure washer can help make the job go faster.
Set the pressure to at least 3,000 psi to eliminate flakes quickly. If you don’t have one, you may be able to rent the device from a local hardware store.
They will also have the protective supplies you need to stay safe.
#5. Repeat as Needed
Be aware that you may have to repeat the above steps. The amount of time needed will depend on how many layers of paint you have to remove. If you are facing an extensive project, you might want to consider hiring a professional.
If you’re dealing with some loose spots and stains on the wall, you will need less time than if you’re removing paint off of a larger surface like an entire garage floor.
If you’re doing a spot treatment, you can make the job more efficient by creating a paste mixture of paint stripper and an absorbent solid, such as pulverized kitty litter or finely ground clay.
You can also opt for non-chemical solutions like a floor buffer or orbital sander.
For nontoxic solutions, try a soda blaster. It’s sort of like a sandblaster, but it emits baking soda (technically referred to as sodium bicarbonate) instead of sand.
Some people prefer to stick to non chemical paint removal methods like soda blasting for environmental reasons.
While it’s challenging to remove old paint from concrete surfaces, it is possible.
You have to be prepared to invest time, effort, and money into the process. It likely isn’t going to be a one-day job and will require multiple hours of labor. Stick to the above steps, be patient, and you can get the job done!