Short answer
To clean a tarmac driveway, sweep it, pull out weeds and moss, then scrub with water and a mild driveway cleaner and rinse. A pressure washer can be used on a low setting and kept moving, but high pressure can strip the fine surface and loosen stones. Keep petrol, solvents and similar products off tarmac, as they can soften it.
How tarmac differs from other surfaces
Tarmac is made of stones held together by a bitumen binder. That binder is what makes it flexible and dark, and it is also why tarmac needs a different approach from concrete. Over time the surface becomes more open, the binder more brittle, and loose stones can appear. Fuel, oil and solvents break bitumen down, and high-pressure water can wash the fine material out from between the stones.
Clean it gently and regularly, and you will avoid most of the problems that come from aggressive cleaning.
Step by step: cleaning tarmac
- Sweep the drive with a stiff broom to clear leaves, grit and loose stones.
- Pull weeds and moss out of cracks and along the edges with a weeding tool.
- Wet the surface with a hose.
- Apply a mild driveway cleaner that is suitable for tarmac, diluted as the label instructs, after testing it on a small area.
- Scrub in sections, focusing on green patches, tyre marks and the area near the road where dirt builds up.
- Rinse thoroughly, working from the highest point downwards, and let it dry.
Using a pressure washer on tarmac
A pressure washer can make light work of the rinse, but treat tarmac with respect. Use a lower setting and a wide fan nozzle, hold the lance well back, keep it moving and never concentrate the spray on cracks, edges or loose areas. A rotary surface cleaner attachment helps you keep a steady distance and avoid stripes. If you see stones or fine material washing out, stop and reduce the pressure.
Older tarmac that is already crumbling or has loose stones on the surface is best cleaned by brushing and rinsing only. Pressure washing a failing surface can speed up the damage.
Moss, algae and weeds
Shaded tarmac often develops green algae and moss, especially along the edges and under trees. Brush them off, rinse, and consider a moss and algae treatment labelled as safe for tarmac. Cutting back overhanging plants and keeping the drive clear of leaves slows regrowth.
Weeds in cracks should be pulled out with their roots. If cracks are wide or spreading, cleaning will not fix them, and they can let in water that makes the damage worse in frosty weather.
Oil, fuel and other stains
Oil and fuel are the main enemy of tarmac because they soften the binder. Soak up a fresh spill straight away with an absorbent such as cat litter or sawdust, sweep it up, then wash the area with warm water and a little detergent. Do not use petrol, white spirit or other solvents to try to shift a stain, as they can dissolve the surface. Our guide to removing oil stains from a driveway explains the options in more detail, but check that any degreaser is suitable for tarmac.
Tyre marks and general grime usually lift with a driveway cleaner and some scrubbing.
Watch out in hot weather
Tarmac softens in heat. Avoid cleaning it in strong sun, avoid turning car wheels on the spot, and keep sharp or heavy point loads such as trailer jacks and skips off it until it cools. Cleaning products also dry too quickly in hot conditions to work properly.
When to call a professional
Call a professional if the drive is heavily stained or green, if you are worried about loosening an older surface, or if there is fuel or oil damage. Cracks, potholes and sunken areas need a surfacing contractor rather than a cleaner.
We clean tarmac driveways with a lighter touch than concrete or block paving, adjusting the pressure and using suitable cleaning solutions to remove algae and staining without loosening the surface.
Rather have it done for you?
Block paving, tarmac and resin driveways cleaned, weeded and re-sanded. Family-run by Jason and Lucas Prior, covering south Essex.
Frequently asked questions
Can you jet wash a tarmac driveway?
Yes, with care. Use a low setting and a wide fan nozzle, keep the lance moving and well back, and stop if stones or fine material start washing out. Brush and rinse older, crumbling tarmac instead.
What removes oil from tarmac?
Soak up fresh oil quickly with an absorbent, then wash with warm water and a little detergent. Avoid solvents and petrol-based cleaners, which can soften tarmac, and check any degreaser is labelled as safe for it.
Why is my tarmac driveway going grey?
Tarmac naturally lightens as the surface weathers and the binder ages. Cleaning removes dirt and green growth but will not reverse weathering, which is a job for a surfacing specialist.
Related guides
- How to remove oil stains from a driveway: what to do with a fresh spill, how to tackle older marks on concrete and block paving, and what never to pour on a drive.
- How to clean a driveway: the general method for any drive, a full walkthrough for concrete, and how to tell which surface you have.
- How to clean a resin driveway: routine care and gentle washing for resin bound and resin bonded drives, and the products and tools to keep away from them.