Can You Pressure Wash an Asphalt Driveway?

Yes, but asphalt is not concrete

Concrete is cement paste locking in sand and stone. Asphalt is stone held together by a petroleum binder that stays slightly flexible. That flexibility is why asphalt handles ground movement well, and also why it does not tolerate aggressive washing. A hard, close stream can wear away the binder at the surface, loosen small stones and leave a rough, pitted patch.

The fix is simple: lower pressure, a wide fan tip or a surface cleaner set up for gentler work, and cleaning solutions doing more of the lifting. You are rinsing dirt off the surface, not scouring it.

A quick check before you start tells you a lot. Rub the surface with your shoe. If small stones come loose easily, or the surface looks gray, dry and crumbly, the asphalt is already worn. Washing will clean it, but loose material will come up with the dirt, and the surface may look rougher afterward. That is a sign it needs sealcoating or repair, not just cleaning.

Heat changes the rules in LA

Asphalt softens as it warms. On a hot summer afternoon in the San Fernando Valley, a driveway in full sun can feel tacky underfoot. Washing it then is a bad idea. The surface is at its weakest, and pressure is more likely to dislodge stone.

Schedule asphalt cleaning for a cool morning, or for the milder months of spring and fall. Water cools the surface as you work, but it does not undo damage done in the first few passes.

Oil stains are a bigger problem on asphalt

On concrete, motor oil is a cosmetic stain. On asphalt, oil is a chemical cousin of the binder and slowly dissolves it. A long-term drip under a parked car can leave a soft, crumbly spot that dents when you press it.

That also limits which degreasers you can use. Strong solvent-based degreasers can soften asphalt the same way the oil does. Use a water-based degreaser or a product labeled safe for asphalt, let it dwell, agitate gently with a brush, then rinse at low pressure. If the spot is already soft or crumbling, cleaning will not restore it. That area needs patching. For concrete, our oil stain guide covers the more aggressive methods that work there.

Cleaning before sealcoating

Sealcoat needs a clean, dry surface to bond. Dust, oil and organic growth all cause peeling. The usual sequence is to clean, treat oil spots with a primer if the sealcoat manufacturer recommends one, let the asphalt dry thoroughly, then seal.

How long to wait depends on the product and the weather, so follow the sealcoat label. In dry LA weather, asphalt usually dries quickly, but shaded areas and cracks hold water longer. Avoid washing right after a fresh sealcoat. Most products need time to cure fully before they should see pressure or cleaning chemicals.

A safe washing sequence

Sweep or blow off loose debris first so stones and sand are not turned into projectiles. Move cars well off the surface and protect nearby windows and doors. Pre-treat oil and organic staining. Pre-wet the surface on warm days. Clean with low pressure in steady, overlapping passes, working downhill so dirty water moves away from cleaned areas. Rinse edges and the apron last.

Block the path to the street. Under Los Angeles Municipal Code section 64.70.02, untreated wash water from paved-surface washing should not be discharged into the storm drain system. Direct runoff to landscaping where appropriate, or contain it.

What results to expect and what it costs

A gentle wash removes dust, tire grime, leaf stains and mildew, and makes faded asphalt look tidier. It will not turn gray, oxidized asphalt black again. That is what sealcoating does. Cracks, potholes and soft oil spots need repair, not cleaning.

For larger asphalt areas such as shared drives and small lots, the closest calculator line is parking lot and concrete cleaning, which is $0.25 per square foot as of October 2026. Residential driveways quote at $0.50 per square foot. Every visit has a $195 minimum, and the instant quote calculator shows a flat price you confirm before work begins.