Oasis FAQs
How much does house washing cost in Southwestern PA?
For most homes in Greene, Washington and Fayette counties, a full exterior soft wash starts around $225 to $275 and scales with square footage, number of stories and how heavy the buildup is. A typical two-story home usually lands in the $400 to $650 range.
We provide a free written quote before any work begins, so you know the exact number up front. No surprise charges on the day of service.
What are the black streaks on my roof and will they damage my roof?
Those streaks are Gloeocapsa magma, an airborne alga that feeds on the limestone filler inside asphalt shingles. It is not just cosmetic. Left alone, it traps moisture against the roof, degrades the shingles, and can shorten the roof’s life. Heavy growth can also become a problem during insurance inspections.
The fix is a soft wash roof treatment. High pressure can strip the protective granules off your shingles, so we never pressure-wash a roof. The treatment kills the algae and the streaks fade, restoring the roof without damage.
When is the best time of year to schedule exterior cleaning in Pennsylvania?
Spring and fall are the two smart windows in our climate. Spring removes winter salt residue and the algae that took hold over the wet months. Fall cleaning preps concrete and siding before freeze-thaw cycles lock stains in for the season.
If you are planning to paint, stain, or seal a surface, schedule the wash first. Clean surfaces bond better and coatings last longer. Our season runs from spring through late fall, and the calendar fills fastest in May and June, so booking a few weeks ahead is wise.
How long do the results last?
For most homes in our region, a house wash keeps siding clean for 12 to 24 months, depending on shade, tree cover and moisture exposure. North-facing walls and heavily shaded properties regrow algae faster. Roof treatments typically hold for several years because the solution kills growth at the root rather than rinsing it off.
Concrete in high-traffic areas benefits from annual cleaning. Businesses with grease, gum or heavy foot traffic usually need a quarterly or monthly schedule to stay presentable.
What is the difference between soft washing and pressure washing?
Pressure washing uses high-pressure water to clean hard surfaces such as concrete driveways, sidewalks, patios, and parking lots.
Soft washing uses low pressure, about the strength of a garden hose, combined with professional cleaning solutions that kill the algae, mold, and bacteria growing on the surface.
The distinction matters because high pressure on the wrong surface causes permanent damage. Vinyl siding, roof shingles, wood, and painted surfaces should always be soft washed.
At Oasis, we assess every single surface before we start and choose the method that cleans without damaging your property.
Will Pressure washing damage my vinyl siding?
It can, and this is the most common damage we see from DIY jobs and inexperienced contractors in Southwestern PA. High pressure forces water behind siding panels, where it feeds mold inside your walls. It also strips oxidized finish unevenly, leaving permanent wand marks you cannot undo.
That is why we never pressure wash siding. Your house gets a soft wash: low-pressure cleaning with a solution that removes green algae and gray grime at the root, not just the surface. The result lasts longer, and your siding stays intact.
Do you offer recurring commercial cleaning programs?
Yes. We build scheduled exterior cleaning programs for restaurants, gas stations, retail storefronts, strip malls, apartment complexes and HOAs across Greene County and the Route 19 corridor in Washington County, including McMurray, Peters Township and Canonsburg.
Recurring service keeps entrances, sidewalks, drive-thrus and dumpster pads clean year-round instead of waiting until buildup drives customers away or creates a slip hazard. We schedule around your business hours, including early mornings and weekends, and bill on a predictable monthly or quarterly cycle.
What areas do you serve?
Oasis Power Washing is based in Waynesburg, PA, and serves all of Greene County, plus Washington County, including Washington, McMurray, Peters Township, and Canonsburg; Fayette County, including Uniontown; and Northern West Virginia, including Morgantown and Fairmont.
Not sure if you are in our service area? Call (412) 404-3400, and we will confirm coverage and quote most jobs over the phone.
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