Should You Pressure Wash Before the Rainy Season?

Every fall we hear the same thing from customers: “Let’s wait until after the rain.” It sounds logical. Why clean the driveway, the walkways or the gutters if a storm is about to come through?

The short answer: yes, you should pressure wash and clean your gutters before the rainy season, and waiting usually makes things worse. Rain doesn’t clean your property. It wets whatever is already there, and in Southern California that’s months of dust, oil, leaves and organic growth.

Rain doesn’t clean, it spreads

After a long dry summer, concrete, pavers, stucco and roofs are covered in a layer of dust, tire grime, pollen and leaf litter. When the first storms hit, that layer turns to mud. It runs down walls, streaks across driveways and settles into the low spots on walkways. Rain also feeds algae, mildew and moss, which grow fastest when surfaces stay damp. A dirty surface going into the rainy season usually comes out the other side looking worse, not better.

Clean concrete is safer concrete when it’s wet

This is the biggest reason to clean before the rain. Algae, mildew, oil drips and built-up grime create a film on concrete and pavers. When that film gets wet, it gets slick. Walkways, stairs, pool decks, driveways and parking areas are where people slip.

Pressure washing removes that film and opens up the surface texture of the concrete again, so it grips better when it’s wet. For homeowners, that means safer steps and walkways for family and guests. For property managers and HOAs, it means fewer slip hazards on common walkways, breezeways and entries during the months they get the most rain.

Gutters need to be clear before the first big storm

Gutters fill up with leaves, pine needles and roof debris all summer. If they’re clogged when the first heavy rain comes, the water has nowhere to go. It spills over the edge, soaks the fascia boards, splashes against the walls and pools around the foundation. Clogged downspouts can also back water up under the roof edge.

Cleaning gutters and flushing downspouts before the rainy season makes sure the first storm drains the way it should. If your property has a lot of trees, a second cleaning partway through the season is worth considering.

Roofs and solar panels

Debris sitting on a tile roof holds moisture against the tiles and in the valleys, and that’s where algae and moss take hold. Clearing the roof before the rain helps water run off cleanly. On solar panels, light rain usually doesn’t wash away the dust and bird droppings. It tends to leave a film that keeps cutting into how much sunlight reaches the cells, so a cleaning before the shorter, cloudier winter days helps your panels make the most of the sun they get.

Is it okay to pressure wash right before it rains?

Yes. Concrete, pavers and stucco don’t need to stay dry after they’re washed. Rain on a freshly washed surface just rinses concrete that’s already clean. The only services that need dry weather afterward are things like sealing or coating, and we’ll tell you if your job falls into that category.

Cleaning before the rain also means less dirt and oil gets washed off your property and into the storm drains when the first storm hits. When we wash, we protect nearby drains and recover wash water where the property or city requires it.

Can you still clean during the rainy season?

Yes. The rainy season in Southern California isn’t constant rain. There are plenty of dry days between storms, and that’s when we keep working. Light rain doesn’t stop most concrete, walkway, gutter and commercial flatwork cleaning, because the surface is getting wet either way.

We do reschedule for heavy downpours, strong wind or lightning, and we don’t walk wet tile roofs. Safety comes first for our crew and your property. If the forecast changes, we’ll reach out and move your appointment to the next good day.

Your pre-rain checklist

• Clean gutters and flush downspouts so the first storm drains properly.
• Pressure wash driveways, walkways, stairs and pool decks to remove slippery algae, mildew and oil film.
• Clear leaves and debris off the roof and out of the valleys.
• Wash the house or building exterior so dirt doesn’t streak down the walls.
• Clean solar panels before the shorter winter days.
• For HOAs and commercial properties, clean common walkways, breezeways, entries and parking areas where people walk in the rain.

Don’t wait for the rain to pass

Postponing until spring means spending the wettest months of the year with slick walkways, overflowing gutters and growth spreading across your concrete and roof. Getting it cleaned now gets your property ready for the rain instead of cleaning up after it.

Foothill Pressure Washing is based in San Dimas and serves homes, HOAs and commercial properties across the San Gabriel Valley, Inland Empire and greater Los Angeles. See our residential services and commercial services, request a free estimate, or call (909) 323-6122.

Frequently asked questions

Should I pressure wash before or after the rainy season?

Before. Cleaning before the rain removes the algae, oil and grime that make concrete slippery when wet, and keeps dirt from streaking and spreading once the storms start.

Will rain ruin a fresh pressure washing job?

No. Rain on clean concrete, pavers or stucco just rinses a clean surface. Only sealing or coating needs dry weather afterward.

When should I clean my gutters in Southern California?

Before the first big storm of the season, usually in the fall. Properties with a lot of trees may need a second cleaning partway through the rainy season.

Do you work in the rain?

Light rain doesn’t stop most concrete, walkway, gutter and commercial cleaning. We reschedule for heavy rain, strong wind or lightning, and we don’t walk wet tile roofs.