Oil Stains

Take a nice clean concrete driveway or pristine garage floor and what does it become? A magnet for oil! The cleaner the concrete the stronger the magnetism it gives out, just as soon as a car so much as looks at the concrete it will drip oil. This simple law of life leads to a question that is often asked, “How can I clean oil stains off concrete”?

If the oil stains are fresh the thing to do is to soak up the surplus oil with sand, clean cloth, kitchen tissue (making sure that you do not spread the oil and further stain the concrete), use kitty litter, or any absorbent material will do providing that it will not react with oil. As soon as all the surplus oil is soaked up clean the concrete with either a solvent like mineral turpentine or a proprietary brand of degreaser. Make sure that you follow the manufacturer instructions when using any brand of degreaser.  Paint stripper is also a useful aid in getting rid of fresh oil stains.

Concrete is very much like a big sponge, as soon as the oil is spilled it tends to soak very quickly into the material, therefore, the longer you leave oil on a concrete surface the harder it will be to clean up. One method that has proved useful in the past has been to use engine degreasers on the stains. Spray or coat the degreaser onto the surface leave for a short time (depends on the product, you must read the instructions) and then hose off with as much pressure as your garden hose will give. It may be necessary to repeat this process a few times and sometimes if the stain is quite old the best result that you can hope for is a paler stain than you started with!

Another method is to make a poultice of two parts of lime and one part of mineral turpentine and a plastic supermarket bag. Simply mix the turps and lime into a thick paste (use rubber gloves and take the usual safety precautions that you use when using any chemicals) spread over the stain and cover with the plastic bag, leave for about eight hours. Remove and repeat if required. Sometimes careful spot bleaching of stains will have a dramatic effect but make sure that the bleach you use says only on the oil stain otherwise it will lighten the colour of the surrounding concrete and make the oil stain stand out as badly as before.

I have also known really house-proud people who will chip out the surface of stained concrete, make a paste of fresh mortar to fill up the hole, this is very extreme! The best way is to prevent the stain happening in the first place by use drip trays under cars that park either in your garage or on the driveway.

Read more from Chris Bennett.