It’s a common quip from classic owners that their cars don’t leak oil, they are merely ‘marking their territory’. Even the most fastidiously-maintained older vehicle can drop fluids occasionally, either as a result of old-fashioned engineering tolerances or drips during maintenance. And while us enthusiasts might see this as a charming reminder of life with a classic, our partners, neighbours and landlords may not see an oily puddle on the block paving in the same way.
This means that eventually you will be forced to divert the pressure washer away from the car and point it at the parking spot instead. In addition to looking smarter, a good clean driveway will also benefit your car, as the sand and grit which accumulate under and around your car will bounce upwards in heavy rain and could stick to their delicate underparts.
While pressure washing will do a lot of the hard work for you, tough stains are going to need a bit of chemical persuasion and a scrub too. We broke out the brush and tried out seven specialist driveway cleaners – which should also be ideal for cleaning patios and terraces. For balance, we also tried some plain old Fairy Liquid.
We applied the products to our grubby concrete driveway which had a combination of Land Rover fluids, moss and general grime. To test it on posher surfaces we also let used engine oil soak into paving blocks. We then attacked them with our cleaners to see what difference they made, both with and without scrubbing and pressure washing.
Bostik Cementone Brick & Patio Cleaner – Winner
Size: 5 litres
The catalogue listing for this Bostik cleaner says it must not be sold to anyone under the age of 18 and the instructions have all sorts of other warnings too. These indicate that it is serious stuff which needs to be treated with care, but it also means it has the power to do the business if used properly.
The ‘secret’ ingredient is acid, which means the Cementone has unbeatable cleaning power, but use it carelessly and you could damage yourself, sizzle bits of your car or find your prized Koi carp floating face up if you let it drain into a pond.
The instructions suggest it can be used diluted and we tried it at 3:1 which makes it decent value too. Pouring it gently using a watering can (while wearing goggles and gloves), it soon starts to fizz on the surface as it dissolves dirt in its path.
A few swishes with the broom and it starts to reveal the clean stone underneath. There are a couple of downsides – it can’t be used with a pressure washer as there is a risk of splashing, and it smells awful. But if you can use it safely, it’s the business.
Swarfega Patio & Driveway Cleaner – Runner up
Size: 5 litres
When any home mechanic needs to get oil and grease off their hands, it’s usually the tub of green and gooey Swarfega they’ll reach for.
The same brand produces a pretty effective way of getting grime off your driveway too. At £12.99 for 5-litres it does look a little on the expensive side, but it is meant to be diluted at 10:1, which means you’ll be able to pass it down to the next generation before it will run out.
Following the instructions, we left the solution to dwell for 20 minutes before trying it with both a scrubbing brush and pressure washer.
It wasn’t as effective or easy to use as our winner on general grime and algae, but it actually removed more of the oil stain – while the Bostik removes the top layer of the concrete to reveal the clean surface, the Swarfega cleans it instead. It is harder work, but we actually worried less about using it on large areas and could deploy the blast of a pressure washer too.
Size: 1.19 litres
We only threw the Fairy into this test as a benchmark, to see if the specialist cleaners were any better than something you already have under the sink. And to our surprise, the mild green stuff was able to burst the bubble of many of the alternatives here.
We wet the surface first and then liberally squirted the Fairy around the surface, before scrubbing with a sweeping brush and then jet washing. A second go on the oiliest patch made it almost disappear.
There are only three drawbacks – it is quite time-consuming, as you need to scrub as well as pressure wash to get the best effect. It’s also not as cheap as it might appear, as we used most of a bottle on a section of the drive. The dilutable cleaners will do one driveway multiple times. The final potential issue is that you might be left with nothing to do the dishes.
Spear & Jackson Path, Patio & Decking Cleaner
Size: 2.5 litres
Amazingly, this Spear & Jackson cleaner is even better value than the Fairy. A the time of testing, it was less than £3 at B&M for a 2.5-litre bottle or £4.99 for a 5-litre. If there’s not a B&M nearby, Homebase has it at the same price. The instructions say it can be diluted at up to 4 to 1 too, so there’s a lot of cleaner for not much money.
There is a drawback though – it contains chemicals which kill moss and prevent the growth of algae rather than any strong detergent to tackle oily stains. This meant it did a great job of getting rid of the green growth but hardly touched the Land Rover’s puddle of shame.
We reckon a cocktail of Fariy and Spear & Jackson could be a budget combo that has the best of both though.
Karcher Stone and Paving Cleaner
Size: 1 litre
The Karcher way of cleaning your drive is definitely a posh option. Instead of messing around with dilution measurements and sprinkling with watering cans, you just attach the bottle of cleaner direct to your Karcher pressure washer. If you have one of the bigger machines, you just invert the bottle and put it in the special slot on top of the washer. On the smaller Karchers you’ll need to insert a feeder hose.
Either way, the solution is fed automatically into the flow of the jet at the correct ratio. After applying using the least aggressive setting on the nozzle, you leave the solution to dwell and then blast using a more powerful jet blast.
It does a reasonable job clearing the greenness and general dirt but needed two goes to get the surfaces really clean and made little impact on the oil stains.
Size: 2.5 litres
We can’t really blame the Patio Magic! (the exclamation mark is part of the name for some reason) for not making the slightest difference to our oily patches as it is only designed to be a mould and algae killer.
There is no need to scrub to make it work, as you just spray it onto the surface using a watering can and it starts to kill the organisms like a weed killer. You then wait a few days until it is all dead and go back to clean it off. It’s meant to prevent regrowth too.
If you are suffering from mould or algae then it is very effective, but you’ll still need another cleaner afterwards to make your drive look smart.
Knockout Mould and Mildew Driveway, Decking & Patio Cleaner
Size: 4 litres
While some of the cleaners here are only detergents and others are only mould and algae killers, this Knockout appears to offer both in one liquid. The trouble is, it doesn’t do either job particularly well.
We followed the instructions carefully, noting that Knockout is not designed to be diluted. This means you need to be very careful to work out how much to use in the sprayer or it will work out expensive, or you run out before you’ve treated the whole driveway.
Even with some scrubbing there was little detergent effect to clean the oil and other grime which led us to believe nothing was happening at all. However, after a few days there was some obvious effect on the moss and algae – but we still had to clean it all again.
The Bostik Brick & Patio Cleaner was so good we didn’t think we’d need to use anything else, but you really do need to treat it with respect or you’ll kill things and damage stuff you really don’t want to damage. But use it carefully and sparingly and it will do the job well with minimum effort.
If you are worried about the wildlife or have a lot of oil on the surface of your drive, then the Swarfega is the best bet, although a small patch can also be treated pretty effectively with Fairy Liquid and some scrubbing.
If your main issue is moss and algae, the Spear & Jackson kills it easily, inhibits regrowth and is amazing value.