How Often Should You Pressure Wash Your Driveway in Thurston County?

If you’ve got lots of trees nearby (especially fir or maple), you might need a cleaning once a year. Moss and algae love the shade. Driveways that get full sun can go longer, maybe every two or three years.

Why shade decides it

Concrete is full of tiny pores, and in our climate they hold water for a long time. Sun dries them out. Shade doesn’t. So the north side of the house, the strip along the fence, and anything under a fir stays damp most of the winter. That’s where the green starts.

You can see it on your own driveway. There’s usually a line where the shade ends, and the clean concrete starts right there.

Here’s what to look for:

• Green patches or moss growing in the cracks
• Slippery surfaces after rain
• Oil stains or tire marks

The slippery part is the real issue

That thin green or black film is algae. Dry, you barely notice it. Wet, it’s like walking on ice, and it’s worse on a slope. Most people call us about how the driveway looks. The better reason is that somebody is going to fall on it.

Pressure washing removes all of that and helps keep the surface safe. If you’ve got kids riding bikes or older folks using walkers, a clean driveway can prevent slips and falls.

Regular cleaning also helps your driveway last longer. Moss can eat into the concrete and cause it to crack over time. Keeping it clean is cheaper than replacing it.

Oil stains are a separate job

Water alone won’t lift oil. Concrete soaks it up like a sponge, so a leak that sat all summer is down in the slab, not on top of it. It takes a degreaser and some patience, and old stains may lighten without disappearing. Fresh ones come out much better. If your car is dripping, deal with the spot this month, not next year.

Doing it yourself

You can rent a pressure washer. Plenty of people do. Two things go wrong.

The first is stripes. A narrow tip held close to the concrete cuts lines into the surface, and those lines don’t wash out. They’re etched in. Pros use a surface cleaner, a round spinning tool that keeps the spray at one height and leaves an even finish.

The second is new concrete. Give a new driveway about a month to cure before any pressure washing. Sooner than that and you can strip the smooth top layer off.

Making it last between cleanings

• Sweep or blow off needles and leaves. Piles of wet leaves hold moisture and leave brown stains.
• Look at where your downspouts drain. If one runs across the driveway, that strip will always be green.
• Cut back branches that keep the concrete in shade all day.

Not sure if it’s time? Send us a photo, we’ll take a look and let you know.