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
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.