There are many ways that paint might end up on a concrete surface. Kids can spill while fingerpainting. A DIY spray paint project might produce overspray. Nail painting during an at-home spa day on the patio might involve a few drips. Whatever the case, these stains can’t stay, and this guide on removing paint from concrete will help.
How to Remove Paint from Concrete using Acetone
One way to remove paint from concrete is to use acetone, which works well for oil-based, acrylic, and enamel paints. Acetone’s available in quart and gallon sizes; you’ll need enough for a few applications for each job.
You’ll also need:
- Thoroughly wash the area with a garden hose or bucket of water to remove any dirt that could affect the acetone’s ability to loosen the paint. Allow the space to dry to prevent dilution.
- Saturate the paint stain with acetone by pouring it directly on top. Allow the acetone to work on the stain for five minutes. Wear gloves, eye protection, and a respirator mask, as acetone can irritate skin, eyes, and airways.
- Apply a bit more acetone to the stain and scrub with the brush. If the concrete is rough, use the wire brush to scrub it. If not, use the stiff-bristled brush and scrub in circular motions.
- Rinse the area with a garden hose or bucket of water. Allow it to dry before repeating the process as many times as necessary.
How to Remove Paint from Concrete Using a Pressure Washer
Pressure washers can be very helpful for removing stains from concrete. Use a pressure washer with a maximum output of at least 3,000 PSI. The water pressure alone is often enough to break the bond between the paint and concrete, but be sure to protect plants and structures in the area.
Professionals often use pressure washers with water heaters to remove paint stains. While these pro-grade tools might be too much of an investment, DIYers can replicate this method by soaking the paint stain in hot (not quite boiling) water.
Heat a pot of water on the stove and pour it over the stain, being careful not to splash or burn yourself. Apply a towel over the stain and soak it in hot water. After a few minutes, proceed with pressure washing as outlined below.
In addition to the pressure washer, you will need:
- Plastic sheeting
- Protective gear (gloves, pants, long-sleeved shirt, eye protection, respirator mask, hat)
- Paint thinner (optional)
- Before starting, be sure to don all safety gear to prevent injuries. Protect plants, furniture, fences, and other structures with plastic sheeting.
- If desired, apply paint thinner to the stained area. Allow it to sit for several minutes to break down the paint’s bond with the concrete.
- Adjust the pressure washer to 2,500 to 3,000 PSI and fit the wand with a 15-degree nozzle (typically yellow). Starting from the stain’s closest edge, hold the nozzle about 12 inches from the ground and spray back and forth. In some cases, the entire paint stain will come off in one large skin. In other cases, it may break down into smaller pieces.
- If needed, apply another round of paint thinner to the remaining nooks and crannies before spraying again in the same manner as above.
Note: If the paint stain is stubborn, reduce the distance between the nozzle and the stain or increase the pressure washer’s output. Do not use the 10-degree nozzle (red), or it could damage the surface.
For oil-based stains, you may need to use paint thinner. This method is less environmentally friendly and can cause injury. Be sure to protect plants, other painted surfaces, and vehicles and ensure children and pets are not in the area. Also, wear long sleeves, pants, gloves, safety glasses, a hat, and a respirator mask to prevent injuries.
How to Remove Paint from Concrete Using a Grinder
Sometimes the paint on the concrete isn’t a spill or accident. It’s an actual coat of paint, which can be much more difficult to remove. Instead of paint thinners and wire brushes, an angle grinder fitted with a diamond wheel will be faster.
You will need:
- Window fan
- Angle grinder with dust collection attachment
- 4.5-inch diamond wheel
- Wet/dry vac with HEPA filter
- Respirator mask
- Leather gloves
- Knee pads
- Eye protection
- This paint removal method will likely create a lot of dust, so set up a window fan, aiming it outward to expel airborne dust. Also, wear gloves, knee pads, a mask, and eye protection.
- Sweep the floor to remove dust and dirt as either will slow down the paint removal process.
- Using the grinder fitted with the diamond wheel and connected to the wet/dry vac, gradually grind the paint off the floor. Keep the grinder moving in side-to-side motions to prevent it from gouging the concrete. Note: If using a corded grinder, keep the cord behind you to prevent accidentally wrapping it up in the grinding wheel.
- Stop frequently throughout the process to ensure the grinding wheel doesn’t clog. Use the vacuum to collect dust; let it settle inside the vacuum before opening the lid.
- In most cases, grinding will not damage the concrete’s surface. But if swirls or grooves are evident after removal, consider renting a concrete polisher to even out the ridges.
Don’t overreact to spilled paint. It’s often better to let the paint dry and harden as one big thick skin than to spread it around with water or a rag.
A final note on stains that resist removal: If a paint stain is so stubborn that no combination of solvents, wire brushes, or pressure washers will remove it, consider giving the entire surface a fresh coat of paint, hiding stains from existence altogether.