A practical schedule
| Surface | How often |
|---|---|
| House siding | Every 12 to 18 months |
| Roof | When black streaks appear, often every few years |
| Driveway and sidewalks | About once a year |
| Patios and pool decks | Once or twice a year |
| Wood decks | Once a year, before sealing if you seal |
| Storefronts and entrances | Monthly to quarterly for busy businesses |
Signs it is time
- Green or black film on the north side of the house
- Black streaks running down the roof
- Dark, slick patches on shady concrete
- Moss growing in paver joints
- Gray, weathered deck boards
What makes it come back faster
Shade, moisture and nearby trees are the biggest factors. Homes close to the water deal with salt film, and every spring brings a heavy coat of pine and oak pollen. Irrigation that sprays siding or concrete also feeds growth.
Best times of year
Late spring, after pollen season, is a popular time to wash the house so it stays clean through summer. Fall is great for concrete and decks before the holidays, and it is also when to book holiday lights.
Frequently asked questions
Does washing more often cost more?
Regular maintenance usually takes less time than cleaning heavy buildup, so staying on schedule keeps each visit simpler.
Should I wash before painting?
Yes. Paint needs a clean surface to bond. A soft wash is a good first step before any exterior painting.