How Often Should You Pressure Wash Your House in Summerville, SC?

Why the clock runs fast here

Growth, not dirt, sets the interval. Algae and mildew need moisture, and this stretch of the coast supplies plenty of it: the NOAA 1991–2020 normals record about 52.5 inches of rain a year at Charleston International Airport, on top of humid summers and mild winters. That is why a house here often shows green on its north wall within a year or two of a wash, where the same house in a drier part of the country could wait far longer.

The interval for each surface

• Siding: every one to two years for most homes. Shaded and north-facing walls come due first, and a sunny, open lot can stretch toward the longer end.
• Roof: every two to four years. A soft wash kills the algae colony instead of lightening it, so the streaks take longer to return than the green on the walls.
• Driveways and walks: every one to two years. Concrete in deep shade, or where rain sits in a low spot, turns slick sooner.
• Decks and fences: no fixed interval on this site; judge them by their color and how the boards feel underfoot.
• Shops and offices: storefronts usually hold up best on a quarterly rotation, and offices need one or two visits a year.

Signs a wash is due, whatever the date

A green or black film creeping up the north side of the house. Dark streaks running down the roof from the ridge. A drive or front walk that feels slippery after rain. Mildew spots under the eaves and on the soffits. A letter from the HOA with a date on it. Any one of those is a better guide than the number of months since the last visit. A yellow spring coat does not count on its own, because it rinses away; the green and black growth underneath it is what tells you the interval has run out.

More washing is not better washing

Washing more often does not buy a cleaner house. Repeated high pressure only strips the surface color, leaves the growth rooted, and wears on vinyl, paint and old mortar each time. The better plan is one proper soft wash on a steady interval, which is what keeping the siding on a one-to-two-year clock means in practice. Let the gap run much longer and the growth roots deeper into the texture of the siding and the joints of the concrete, and a heavily built-up house can move onto a higher price line.

How often, not when

This page is about the gap between washes, measured in years. The best week of the year to book one, around the spring pollen, is a different question with its own answer in the Summerville pollen timing guide. If your house is overdue now, send photos of the worst wall and the roof, or call (843) 994-2432, and one independent washing company gets the request and prices it.