Direct answer: Pressure washing relies mainly on water pressure to remove buildup from durable surfaces such as sound concrete. Soft washing relies on lower-pressure application and surface-appropriate cleaning solutions, followed by a gentle rinse. The correct method depends on the material, its condition, the contaminant being removed, and the manufacturer’s cleaning instructions.
Answered by Eric Grooms, owner of Upper Cumberland Pressure Washing. Eric founded the Cookeville-based company in 2019 and serves residential and commercial properties across the Upper Cumberland.
Published: August 31, 2026
Last reviewed: August 31, 2026
From Eric’s firsthand job experience, added September 12, 2026.
How I choose the method on a real job
In our work, we reserve traditional pressure washing for suitable concrete and stone. We use our softwash system on house siding and other delicate surfaces, letting the cleaning solution do the work rather than relying on high pressure. Customers are often surprised that low-pressure cleaning can remove the algae that makes a house look dirty.
When stone or mortar needs a gentler approach
I look at how the stones are stacked, whether they appear to have moved, and whether any mortar is brittle. Painted brick or stone also needs care because high pressure can chip the paint. Where the surface can still be cleaned, we usually choose a gentler treatment and a light rinse. If mortar is visibly breaking away, we may decline to wash that area and explain that cleaning could cause more damage.
How we reach upper stories without ladders
We use commercial-grade softwash pumps, with reach of up to 65 feet from the ground when site conditions allow. Some commercial work requires lifts. Wind is our biggest limiting factor; trees can obstruct access, although we can often work around them. We may wait for a lull to clean a particular area. If there is no workable break in the wind, we may reschedule.
Does a house wash remove oxidation?
No. A standard house wash cleans the home but does not remove oxidation. One check we use on vinyl siding is rubbing a finger across it: a chalky residue indicates oxidation. We offer oxidation removal as a separate, specialized service and demonstrate the expected result on a small, inconspicuous area before the customer decides.
We sometimes see what we call “Zorro stripes”: uneven marks where previous high-pressure cleaning has disturbed the oxidized surface. More pressure is not the answer to that problem. Rust also needs its own assessment and specialty treatment; it is not ordinary algae removal.
Soft washing and pressure washing compared
| Consideration | Soft washing | Pressure washing |
|---|---|---|
| Main approach | Low-pressure application with a suitable cleaning solution and gentle rinse. | Controlled water pressure, with treatment selected for the buildup. |
| Typical surfaces | Suitable siding, painted surfaces, and asphalt-shingle roofs. | Sound concrete and other durable surfaces that tolerate pressure. |
| Before cleaning | Check material, finish, condition, and manufacturer instructions. | Check age, coatings, cracks, and condition before choosing pressure. |
| Gutters | Exterior gutter washing covers outside surfaces. | Inside gutter cleanout is separate work; it is not included in an exterior wash. |
When pressure washing makes sense
Pressure washing is commonly used on durable exterior materials, including sound concrete, certain masonry surfaces, and other substrates that can tolerate controlled pressure. The operator still needs to choose the correct nozzle, working distance, flow, and cleaning pattern.
Using more pressure is not automatically better. Pressure-washer manufacturer SIMPSON advises selecting the nozzle for the surface, beginning farther away, moving closer gradually, and stopping if damage appears.
When soft washing makes sense
Soft washing is generally the better approach when high pressure could force water behind a surface, remove a coating, loosen roofing granules, or leave visible wand marks. Examples may include vinyl siding, painted surfaces, and asphalt shingles.
The Vinyl Siding Institute says a power washer may be used on some siding, but only with caution and according to the siding manufacturer’s instructions. It warns against aiming water upward because water can be forced behind the panels.
For asphalt shingles, the Asphalt Roofing Manufacturers Association says cleaning solution should be gently applied and warns against scrubbing. Its roof-cleaning guidance says not to use a pressure washer on asphalt shingles because it can cause granule loss.
Why the surface must be inspected first
The same cleaning method is not appropriate for every property. Before cleaning, look for loose mortar, failing paint, oxidized siding, cracked concrete, damaged caulk, open electrical components, and areas where water could enter.
The safest plan follows the material manufacturer’s instructions and begins with the least aggressive effective method.
Important limitation
“Soft washing” is an industry term, not one universal procedure. Equipment, solution strength, dwell time, plant protection, and rinsing requirements vary. Manufacturer instructions and on-site conditions should take priority over a generic recommendation.
For help choosing the right process, review our house-washing service or request a free estimate. Browse more practical guidance in Eric Answers.