How Often Should You Pressure Wash Your House?

Most homes benefit from a soft-wash once every 12 to 24 months, but the right cadence depends on a few things you can judge yourself.

What speeds up the grime

Humidity and shade are the biggest factors. In hot, humid regions, algae and mildew take hold on north-facing and tree-shaded walls far faster than on sunny, dry exposures. Homes near lakes, the coast, or heavy tree cover collect organic growth and pollen more quickly, and salt air adds its own film near the water.

A simple schedule

• Every 12 months in a humid climate with lots of shade, or near water.
• Every 18 to 24 months for sunnier lots in drier climates.
• Spot-treat north-facing walls, gutters, and the roof line as soon as you see green or black streaks starting.

Soft wash, not blast

Siding, stucco, and roofs should be cleaned with low-pressure soft washing and the right cleaning solution, which kills the algae at the root so it stays gone longer. High-pressure blasting can force water behind siding, etch concrete, and strip paint.