pressure-washing
How Often Should You Pressure Wash a House in Missouri? A Surface-by-Surface Schedule
Most Missouri homes need a wash every 12 to 24 months. See a surface-by-surface schedule, signs it's time, and the best months to clean around pollen and heat.
In This Article
How Often Should You Pressure Wash a House in Missouri? A Surface-by-Surface Schedule
Most Missouri houses need a full exterior wash every 12 to 24 months. Homes under heavy tree cover in the Ozarks or along the river bluffs often need it every year, while a sunny vinyl house on an open lot in a newer Kansas City suburb can stretch closer to two years. The right interval depends less on the calendar and more on shade, trees, and what your house is made of.
Missouri summers do most of the damage. July and August regularly bring 90-degree days with sticky humidity, and that damp warmth is exactly what mildew and algae need. Add a spring pollen season that turns cars yellow and a fall leaf drop that leaves tannin stains on concrete, and the outside of a house gets dirty faster here than in drier states to the west.
What Makes Missouri Houses Dirty So Fast
Oak pollen is the first wave every year. From roughly April into May, oaks, hickories, and maples release enough pollen to coat siding, decks, and window screens. On its own, pollen rinses away easily, but it gives mildew something to feed on once summer humidity arrives.
Tree sap follows. Maples, sweetgums, and the shortleaf pines common in southern Missouri drip sticky residue onto driveways, decks, and roofs below them. Sap traps dirt and turns black over a few months, which is why the area under a big maple often looks worse than the rest of the property.
Humidity finishes the job. Green algae shows up first on north-facing walls and the shaded sides of fences, then spreads to gutters, soffits, and the lower few feet of siding where splash-back keeps things damp.
Brick Homes in St. Louis
St. Louis is a red brick city. Neighborhoods like Soulard, Tower Grove, and the Hill are full of older brick homes, and many inner-ring suburbs like University City and Webster Groves have brick fronts too. Brick hides dirt well, so owners often wait too long.
Older brick and soft lime mortar should be cleaned gently, about every two to three years for most homes. Moss and black staining on the north side can show up sooner, especially under tall trees, and that side may need attention every 12 to 18 months.
Vinyl in Kansas City and Springfield
Newer subdivisions around Kansas City, Lee's Summit, and Springfield lean toward vinyl siding. Vinyl shows mildew and dirt quickly, especially lighter colors like white, beige, and pale gray. Most vinyl homes look their best with a soft wash every 12 to 18 months.
Lots on the edges of these cities are often more open, which helps. A south-facing vinyl house with no tree cover may only need a wash every two years.
A Missouri Pressure Washing Schedule by Surface
Every surface around a house ages at its own pace. The schedule below is a general guide for Missouri conditions, and shaded or wooded properties should lean toward the shorter end of each range.
| Surface | How Often in Missouri | Notes |
|---|---|---|
| Vinyl siding | Every 12 to 18 months | Soft wash, more often on north sides |
| Brick | Every 2 to 3 years | Gentle method, watch older mortar |
| Wood deck | Every year | Clean in spring, seal every 2 to 3 years |
| Concrete driveway | Every 1 to 2 years | Sooner under trees or with oil stains |
| Asphalt shingle roof | Every 3 to 5 years | Soft wash only for black streaks |
| Wood or vinyl fence | Every 1 to 2 years | Shaded runs need it yearly |
| Patio and walkways | Every year | Algae makes them slick |
Siding
Vinyl, fiber cement, and painted wood siding should be soft washed, which uses low pressure and a cleaning solution rather than a strong jet. That keeps water from getting behind panels and avoids stripping paint. In Missouri, a yearly wash on the shaded sides and a full wash every other year works well for many homes.
Fiber cement and painted wood can usually go a little longer than vinyl, since they hold color better and show less film. Gutters and soffits are worth checking during each wash, because black streaks on the gutter face, often called tiger striping, need a separate cleaner and a bit of hand scrubbing.
Decks
Decks take the hardest beating because they are horizontal, often shaded, and covered in pollen, leaves, and sap. A yearly spring cleaning keeps algae from making boards slippery and prepares the wood for sealing.
Pressure-treated pine is the most common deck wood in the state, and it should be cleaned at low pressure to avoid splintering. Composite decks need cleaning too, since mold can grow on the dirt that settles on top.
Driveways and Patios
Concrete in Missouri goes through freeze and thaw cycles every winter, and salt from icy roads in Kansas City and St. Louis tracks onto driveways. Cleaning every year or two removes salt residue, leaf stains, and the black algae that grows in shaded spots.
Sealing concrete after a wash, every two to three years, helps it shed water and resist cracking. Patios under trees benefit from a yearly clean because algae can turn them slick by midsummer.
Roofs and Fences
Black streaks on asphalt shingles are caused by algae and show up on many Missouri roofs within a few years. These should be soft washed with no high pressure, usually every three to five years. Fences along wooded property lines in the Ozarks or along creeks grow green algae quickly and often need yearly attention.
Wood fences need a lighter touch than vinyl. Too much pressure raises the grain and leaves a fuzzy look, and a stained cedar fence may need a fresh coat after cleaning, so many owners time the fence wash to their staining schedule, about every three years.
Shade, Woods, and Ozarks Lots
Homes around Lake of the Ozarks, Branson, and the hills south of Rolla often sit under a full canopy of oak and hickory. These lots stay cool and damp, and sun rarely reaches the siding for long. Mildew can return within six to nine months of a wash.
Owners on thickly wooded lots usually do best with a yearly house wash and a mid-season rinse of decks and walkways. Trimming branches so they sit at least 5 to 10 feet from the house cuts down on sap, leaf litter, and shade, and it often stretches the time between cleanings.
Lake homes face one more factor. Moisture rising off the water keeps docks, boathouses, and lakeside walls damp, so they tend to grow algae faster than the rest of the property.
Signs Your House Needs a Wash Now
Calendars are only a rough guide. These signs mean it is time no matter how long it has been:
- Green or black streaks on the north side of the house
- A chalky residue that rubs off on your hand
- Dark spots or slippery patches on the deck or patio
- Black streaks on the roof that are spreading
- Spider webs and wasp nests crowding the eaves and soffits
Faded paint and chalky siding are worth a closer look. Sometimes a wash brings the color back, and sometimes it shows that the siding or paint is near the end of its life. Either way, it is better to know before a home sale or a painting project.
Smell can be a clue too. A musty odor near a shaded porch or a north-facing entry often means mildew has built up on the siding and trim, even if it is hard to see from the driveway. In older St. Louis homes, check the brick just above the foundation, where splash-back and shade keep the masonry damp and moss tends to start.
The Best Months to Pressure Wash in Missouri
Late May through June is the most popular time. By then the worst of the oak pollen has dropped, temperatures are warm enough for cleaning solutions to work, and the house will look good for summer. Washing in early April usually means doing it again a few weeks later once the pollen hits.
September and October are a close second. The summer's mildew growth is at its peak, temperatures are mild, and crews are less busy, so scheduling is easier. Washing in the fall also removes algae before winter, when it can settle in and stain.
Midsummer heat is the main thing to avoid. On a 95-degree afternoon in St. Louis, cleaning solutions can dry on the siding before they are rinsed, leaving streaks. Most crews work early in the day during July and August.
A Quick Word on Cost
A professional house wash in Missouri typically runs about $300 to $600, with decks, driveways, and roofs priced separately. Washing on a regular schedule often costs less over time, since light buildup comes off faster than years of growth.
If you want more seasonal home care tips, browse our full library of Missouri home guides. You can also compare local pressure washing companies in Missouri and ask each one what schedule they recommend for your house.
Missouri Pressure Washing FAQ
Can I wash my house every six months?
You can, but most Missouri homes do not need it. Twice a year makes sense only for deeply shaded houses near lakes or rivers, where mildew can return within a few months.
Does pressure washing damage brick?
It can if the pressure is too high, especially on St. Louis brick homes with original lime mortar. A soft wash or low-pressure rinse with a detergent is safer and still removes most dirt and algae.
Should I wash before or after the fall leaves drop?
After is usually better for driveways and patios, since tannin stains from wet oak leaves show up in October and November. For siding, an early fall wash in September works well before temperatures drop.
Is it worth cleaning the deck every year?
For most Missouri decks, yes. A yearly cleaning in spring removes pollen and algae, prevents slippery boards, and helps a sealer last two to three years instead of one.