How Often Should You Pressure Wash Your House in Northern Virginia?

Short answer: most homes in Northern Virginia look their best with a professional house wash every 12 to 24 months. Homes with heavy shade, nearby woods or walls that stay damp often need it every year. Homes in full sun with newer siding can sometimes go longer.

The right schedule for your home depends on a handful of factors that are especially relevant in NOVA.

Why Northern Virginia homes get dirty faster than you’d expect

Northern Virginia has a humid summer climate, a long and heavy spring pollen season, and a lot of mature tree cover — especially in places like Reston, Vienna, McLean and the wooded parts of Fairfax and Loudoun counties. That combination creates ideal conditions for:

• Green algae — the green film that shows up on shaded siding, often on the north side of the house
• Black mildew — dark spots and streaks under eaves, around gutters and behind shrubs
• Pollen and dirt — the yellow-green layer every spring, which then traps more dirt
• Red clay splashback — reddish staining on lower siding near mulch beds, common in Loudoun County

Factors that change how often you should wash

Shade and tree cover

Shade is the biggest single factor. Siding that never gets direct sun stays damp longer after rain and dew, and algae grows back faster. If you can see green on one side of your house within a year of cleaning, plan on an annual wash.

Siding type

• Vinyl shows algae and dirt clearly and cleans up very well with a low-pressure house wash.
• Fiber cement holds paint well but still collects mildew and dirt.
• Brick hides dirt longer, but shaded brick can grow moss and algae, and white efflorescence can appear.
• Painted wood should be kept clean to protect the paint, but it needs gentle cleaning.

Location and surroundings

Homes near busy roads, construction or the Dulles corridor collect more dust and grime. Homes near water, woods or open fields often see more organic growth. Townhouses with shared walls and close neighbors can also trap moisture in narrow side yards.

Your goals

If you’re getting ready to sell, hosting a big event, preparing to repaint or responding to an HOA notice, you’ll want a wash regardless of the calendar.

Signs it’s time to wash your house

• Green, black or gray streaks, especially on the north side
• Visible film when you wipe the siding with a damp cloth
• Cobwebs and insect residue around lights, eaves and windows
• Siding that looks dull or a shade darker than it used to
• An HOA maintenance notice

A simple schedule that works for most NOVA homes

Pressure washing or soft washing?

For siding, “pressure washing” is a bit of a misnomer. Siding should be cleaned with low pressure and appropriate cleaning solutions — often called soft washing — rather than high pressure, which can force water behind panels or damage older siding. Learn more in Pressure Washing vs. Soft Washing.

When to schedule

Spring (after the heaviest pollen) and early fall are the most popular times in Northern Virginia. See the best time of year to pressure wash a house in Virginia for the details.

Ready to get your home on a schedule? Request a house washing quote — it takes about five seconds.