They sound like the same service. They are not, and using the wrong one is how driveways get striped, roofs get destroyed, and paint gets stripped off stucco.
The difference is simple: pressure washing cleans with force. Soft washing cleans with chemistry. One blasts the surface. The other kills what's growing on it and rinses it away.
Pressure Washing
High-pressure water, typically in the 2,000 to 4,000 PSI range, delivered through a narrow tip or a surface cleaner. It removes material physically - ground-in dirt, tire marks, oil residue, and surface staining.
It's the right tool for hard, non-porous, structurally solid surfaces: concrete driveways, sidewalks, paver patios, block walls, and some hardscape. These can take the force without damage, and force is what shifts embedded grime.
What it's not good at is killing anything. Blasting algae off a surface removes what you can see and leaves the root structure in the pores. It grows straight back - often faster, because the surface is now more porous than it was.
Soft Washing
Low pressure - roughly 100 PSI or less, about what comes out of a garden hose - combined with a cleaning solution that actually kills the organism. The solution does the work. The water just carries it on and rinses it off.
This is the correct method for anything porous, painted, delicate, or alive with growth: roofs, stucco, painted siding, vinyl, screen enclosures, wood fences, and natural stone.
Because it's killing the organism rather than removing its surface layer, results last considerably longer. A soft-washed roof stays clean far longer than a pressure-washed one, and doesn't lose granules in the process.
Why Getting It Wrong Is Expensive
Roofs. High pressure strips the protective granules off asphalt shingles and can crack, chip, or displace barrel tile. It also drives water under the tile where it doesn't belong. Most roofing warranties are void the moment someone pressure washes the roof. The Asphalt Roofing Manufacturers Association's guidance is low-pressure cleaning only.
Stucco and paint. Stucco is porous by design. High pressure forces water into the wall and can blow out sections of the finish. On painted surfaces it lifts the paint outright.
Travertine and natural stone. Softer than concrete and far easier to etch. Aggressive pressure leaves a permanently pitted texture that no amount of cleaning fixes.
Wood. Pressure carves out the soft grain between the harder rings, leaving a furry, splintered surface. It looks clean for a week and then weathers badly.
How to Tell What a Contractor Is Actually Doing
Ask two questions before anyone starts.
"What PSI are you running on this surface?" If the answer is the same number for your driveway and your roof, walk away. Different surfaces require genuinely different setups.
"What are you putting on it?" A real soft wash uses a cleaning solution. If someone says they're soft washing your roof with plain water at low pressure, that isn't soft washing - that's rinsing, and the streaks will be back within months.
A red flag worth knowing: anyone who quotes a whole-property price without asking what the surfaces are made of. Travertine, barrel tile, stucco and concrete need four different approaches, and the person quoting should want to know which they're dealing with.
What Most Properties Actually Need
Both, on different surfaces, in the same visit. A typical Miami home is pressure washing on the driveway and walkway, and soft washing on the roof, stucco, and screen enclosure.
That's how we quote it - matched to material rather than a single setting for the whole property. You can see the breakdown by surface on our services page.