There are several ways to remove oil stains from concrete. Oil stains on concrete floors, driveways, or footpaths are unsightly and potentially hazardous. Cleaning the oil will not only make your house look better but may also help you to avoid a nasty slip in wet weather.
Even if you plan to paint, seal or skim the concrete surface, removing the existing oil stains is important. The oil could seep up through the new surface treatment, ruining your hard work.
Here are a few different methods to remove oil stains from concrete surfaces.
Soaking Up a Fresh Oil Spill
When you spill oil, it is best to clean it immediately. If the oil is allowed to soak into the concrete and start to dry out, it will be much harder to remove later.
Small spills can be soaked up with a rag or sponge. Get as much of the excess oil off the surface as you can. If you have some to hand, liberally sprinkle baking soda on the stain to soak it up. Leave it for a while and then sweep up the pile of powder.
If the oil spill is over a larger area, cat litter is a good moisture absorbent. Pour the cat litter all over the oil puddle, enough that it is completely covered. Grind the cat litter into the oil with your feet (suitably protected, of course), and then leave it overnight. If the oil spill is outside, use a plastic sheet to cover the cat litter to protect it from wet weather.
Use a shovel to scoop up the oil-soaked cat litter and dispose of it appropriately. Move on to one of the cleaning methods shown below, before the oil seeps into the concrete further and begins to dry.
Washing Up Liquid and Elbow Grease
Washing up liquid is great for breaking down grease and oil on dishes, and it will do a similar job on engine oil. Squeeze the liquid detergent onto the oil stain and let it stand for an hour.
Use a stiff wire brush to work the liquid into the stain and leave it for another hour. Wipe the excess away with a damp rag. Hopefully, the worst of the oil will also be cleaned away at this stage. Add small amounts of water if needed, and keep scrubbing.
This works best on oil stains that are fresh or still wet, but it can also make a noticeable difference to older oil stains. If you have no washing-up liquid, try using laundry powder instead. This has the added benefit of being slightly abrasive when scrubbed into the stain.
Use a Chemical Concrete Cleaner
You can buy chemical oil cleaning solutions for use on concrete. These are usually fairly expensive but should go quite a long way. Some are even suitable to be diluted and used in a pressure washer.
Chemical driveway or concrete cleaners usually need to be applied to the stain neat and left for a short time. It can then be washed off with water, hopefully taking the oil stain with it. Multiple applications might be needed on large or very old stains.
This type of degreaser uses strong chemicals, so protective equipment should be worn when applying it.
Get a Professional Cleaner In
Although it goes against the DIY ethic, sometimes it is worth letting someone with all the right gear do the job. Paying someone to clean your concrete garage floor or driveway may be fairly expensive. But it could end up being good value if the stain is large, or if your own cleaning efforts haven’t worked.
Not all professional cleaners will take on oil stains on concrete, especially if they are outside. Call a few and make sure they know what you need.
Cleaning Oil Stains From Concrete
It might be hard work, particularly if the stain is old, but it is certainly possible to remove oil from a concrete floor. The key is to use some sort of degreaser to break up the stain, before washing it away. And once you have cleaned the oil, consider protecting the concrete from further staining.