Soft washing is how exterior walls should be cleaned in Agoura Hills: low pressure, the right solution, adequate dwell time, and a gentle rinse. It handles the organic growth and film that pressure cannot remove without damage, and on siding, painted surfaces, and stucco it is the only appropriate method.
Quick answer
Soft wash kills mildew, algae, and bacteria on exterior surfaces using low pressure (~500 PSI) and a biocidal cleaning solution.
The checklist is the same everywhere. What is on your glass is not. These are the conditions that actually shape this job in Agoura Hills. Each one is true here and false in plenty of other towns we serve.
Siding and painted surfaces have seams, laps, and fasteners. High pressure drives water past the surface into the assembly behind it, and it does not dry out from there. The result appears weeks or months later as blistering, staining, or a moisture problem that gets blamed on something else. Soft washing puts the work on the chemistry instead of the force, which cleans more thoroughly and leaves the wall intact. In Agoura Hills this is not a preference, it is the correct method.
May and June are the two cloudiest months of the year on this coast, running about fifty-nine and fifty-eight percent sunny days respectively, and Agoura Hills sits far enough inland that the layer burns off by late morning most days. Fog is not rain. It does not rinse anything. What it does is wet the dust already on the glass, hold it there through the morning, and then dry it into a mottled film when the sun finally comes through. That is why so many Agoura Hills windows look worse in June than in September despite nothing new landing on them. It also changes how the work gets done: exterior glass cleaned into a marine layer dries slowly and unevenly, so we work the sun side first and come back to the shaded elevations, rather than cleaning the house in a circle and leaving streaks on the north face.
Agoura Hills sits in or against the wildland urban interface, which means that in some years the deposit on the glass is not dust at all. Wildfire residue is a mix of fine carbon, alkaline ash, and condensed organic tars, and it behaves nothing like road film. The ash is caustic enough that letting it sit wet on glass etches it, the tar fraction is oily and smears rather than lifting, and the carbon is abrasive. Wiping a smoke-filmed window dry is the single fastest way to scratch it permanently. The right sequence is a flooded neutral-pH pass to carry the alkaline fraction off before anything with an edge touches the pane, then a separate solvent step for the tar, then the actual wash. It is genuinely a different job than a maintenance clean, we quote it as one, and we will tell you honestly when a pane has been etched past what cleaning can fix.
Agoura Hills is on Las Virgenes Municipal Water District, one hundred percent imported Metropolitan supply. Colorado River Aqueduct water arrives at roughly sixteen grains per gallon after evaporating its way across two hundred and forty miles of open aqueduct, which puts it at the hard end of "very hard" by any standard. Every sprinkler pass that clips a pane, every hose rinse, every window washed and left to air-dry in the sun leaves that mineral behind. Combine it with seven months a year of no rain and you get the defining Agoura Hills glass problem: not dirt, but a bonded carbonate film that washing does not touch.
Low-pressure (~500 PSI) wash of every exterior surface: vinyl, fiber-cement (Hardie), stucco, painted wood, brick, masonry. Hardware-friendly: trim, gutters, soffit, and fascia all included.
Biocide application: sodium hypochlorite-based solution (the standard for soft-wash) that kills mildew, algae, lichen, and the black/green biological staining you see on shaded north-facing walls.
Plant and lawn protection, surfactant rinse during application, then full rinse-down at the end so nothing carries to your landscape.
Window pre-coat, we coat windows with plain water before the biocide so any drift doesn't streak the glass. We can also include the windows in the same trip, soft wash + window cleaning is a popular combo.
Optional add-ons: deck soft-wash, fence soft-wash, full-property bundle with driveway pressure wash.
Enter your address. Our autoquoter sizes the home; we'll confirm siding type and any add-ons when scheduling.
Plant covers, lawn pre-rinse, window pre-coat (plain water). Pets indoors. We tape any wall outlets or vents that need protection.
Top-down soft-wash with the biocidal solution. Dwell time 5-15 minutes, long enough to kill the biological staining, not long enough to damage paint.
Plain-water rinse from top to bottom to remove all solution and dead biological material. We watch for any streaking and re-apply if needed.
Walk-around to confirm clean coverage, plants and lawn rinsed, no overspray on neighbors. Before/after photos emailed.
Most Agoura Hills properties land between $590 and $1325 for this service. That band is derived from real Agoura Hills jobs, not a national average, which is why it differs from the number you would see on our page for a neighboring town. Here is how the job profiles break down:
Want the exact number for your address? Get an instant quote in 30 seconds , no callback and no in-home estimate.
Equestrian and semi-rural properties where an address routinely includes barns and outbuildings with glass, plus arena dust year round.
Established production housing with tile roofs and mature landscaping reaching ground-floor glass.
Hillside streets with downslope view glass and full canyon wind exposure.
Association housing with common landscape on recycled irrigation adjacent to ground-floor windows.
Retail and office frontage plus the strongest wind funneling in the city.
Direct wildland interface with grit, chaparral litter and smoke residue in fire years.
See every neighborhood and the full local guide on our Agoura Hills window cleaning page.
Colorado's freeze-thaw cycle is brutal on siding and stucco, water gets into hairline cracks during the day and freezes at night, expanding the cracks and creating perfect conditions for algae and mildew to colonize. Annual soft-wash kills the colonization at the root.
North-facing walls get little direct sun and stay damp longer after snow or rain. That's where Front Range homes show the worst biological staining. Soft-wash is the only safe way to clean these surfaces without damaging the substrate.
Heavy hail (Boulder, Fort Collins, Loveland), hail-dimpled siding catches more biological growth in the dimples. Post-hail soft-wash slows the colonization significantly.
Pressure washing uses force; soft washing uses chemistry at low pressure. Hard surfaces like Agoura Hills driveways and walks take pressure fine. Walls, siding, painted surfaces, stucco, should never take it, because pressure drives water into the assembly where it causes damage that shows up later. Soft washing cleans those surfaces more thoroughly and does not put moisture where it does not belong.
A season to two years depending on exposure. North and shaded elevations regrow first because they hold moisture. The reason a soft wash lasts longer than a pressure wash is that the solution kills the organic growth rather than just removing what is visible, pressure leaves the biology behind and it comes back within months.
Soft wash uses low pressure (~500 PSI) and a biocidal cleaning solution. Pressure wash uses high pressure (~3,000 PSI) and mechanical force. Soft-wash is for siding, stucco, painted wood. Anything that high pressure could damage. Pressure wash is for concrete, brick, and other durable hard surfaces.
Most homes run $300–$800. A typical 2-story 2,000 sqft home is $400–$550. Bundling with window cleaning saves 10-15% on both. Larger homes (3,000+ sqft) or full-property bundles run higher.
No, when done properly. We pre-rinse plants and lawn before applying the biocide, use a surfactant during application, and do a full final rinse so nothing accumulates. Plants are the same green color when we leave as when we arrived.
It kills the current colonization completely. New algae will eventually colonize again, typically 12-18 months in Colorado, faster on north-facing walls in shaded yards. Annual or bi-annual soft wash keeps it at bay.
Get your free quote in 30 seconds.
Get Instant QuoteOr call anytime: 303-990-2878