Soft Washing vs Pressure Washing, Surface by Surface
Garner Pressure Washing • July 12, 2026 • 9 min read
Most articles on soft washing vs pressure washing give you the contractor’s opinion: soft washing for siding and roofs, pressure for concrete, trust us. That rule of thumb is broadly right, but it skips the part that actually settles arguments. The companies and trade bodies that make shingles, brick, fiber cement and pavers publish their own cleaning instructions, and several of them name a pressure, a nozzle or a flat “do not.”
This page puts those published rules in one table, with the source for each line, so you can check any quote or any rented machine against what the maker of your surface says.
That matters on a typical Garner lot, because one house can carry four or five different rulebooks. A home in Adams Point might have an asphalt shingle roof, a brick skirt, fiber cement on the front gable, vinyl on the sides, a poured concrete driveway and a paver patio out back. Each surface has its own limit, and “soft wash” or “pressure wash” is too blunt a label for all of them.
What Is the Real Difference Between Soft Washing and Pressure Washing?
The difference is where the cleaning power comes from: soft washing relies on a cleaning solution and dwell time, and pressure washing relies on the force of the water. Soft washing applies a solution at low pressure, lets it work, and rinses gently. Pressure washing removes buildup mechanically, which is why it suits hard, dense surfaces and harms soft or coated ones.
What neither term gives you is a number. None of the manufacturer or trade body pages cited below defines “soft washing” by a pressure figure, and “pressure washing” covers everything from a gentle rinse to a narrow jet that can cut wood. The step-by-step method of a soft wash is on the house washing service page, so it is not repeated here.
What Pressure Does Each Surface’s Maker Allow?
Every source below either names a pressure range or says no high pressure at all, and none of them approves high pressure on shingles, brick or fiber cement. Here is what each one publishes, checked on 26 September 2026:
| Surface | Who publishes the rule | What they say about pressure | Cleaning solution they describe |
|---|---|---|---|
| Asphalt shingle roof | Asphalt Roofing Manufacturers Association (ARMA) | “Never use a pressure washer.” Rinse with low-pressure water | 50:50 laundry-strength chlorine bleach and water, 15 to 20 minutes of dwell |
| Asphalt shingle roof | GAF, Technical Bulletin TAB-R-102 | No power washing; rinse at low pressure | Water, bleach and TSP (or a substitute) from a garden sprayer, up to 20 minutes |
| Brick walls | Brick Industry Association (BIA), Technical Note 20 | Pre-wet under 100 psi; rinse at 100 to 400 psi; 400 to 800 psi only if the brick maker permits; over 800 psi “is not appropriate for brick” | Chosen by stain and brick type; trial a small area first |
| Fiber cement siding | James Hardie | ”Don’t use a high-pressure power washer.” Garden hose and a soft, nonmetal brush | Mild dish soap and water; a mildew cleaner used per its label; “do not use harsh chemicals, such as bleach or acid” |
| Concrete pavers | Interlocking Concrete Pavement Institute (ICPI), Tech Spec 5 | Sprayers apply water at 1,000 to 4,000 psi; use a wide spray and a low angle so joint sand stays in | Paver cleaners matched to the stain |
Sources: ARMA on algae and moss, GAF TAB-R-102, BIA Technical Note 20, James Hardie cleaning tips, ICPI Tech Spec 5 via CMHA.
Two common Garner surfaces are missing on purpose. Vinyl siding makers publish their own care sheets, and none was checked for this page, so no number is given here; the method case for vinyl is in our guide to removing green algae from vinyl siding. Poured concrete is the one surface where high pressure through a rotary surface cleaner is normal practice, but that is trade practice, not a published limit, so it stays out of a table of published rules.
What Does the Table Tell You That a Rule of Thumb Does Not?
It tells you that pressure is only one of three variables, that “soft wash” is not one chemistry, and that the most forgiving surface has its own trap.
Pressure comes with distance and angle. BIA does not stop at psi. It specifies a 25 to 50 degree fan tip held at least 12 inches from the brick, and says pressure should be measured at the nozzle tip. ICPI’s advice for pavers is about spray width and angle as much as force. A narrow tip held close can do more harm at a modest setting than a wide fan at a higher one, which is why a psi number on a rental machine tells you very little on its own.
The chemistry changes by surface. The roof bodies describe a chlorine bleach solution. James Hardie says not to use bleach on its siding at all and points to mild soap or a labelled mildew cleaner instead. So a contractor who runs one mix across roof, brick and fiber cement is ignoring at least one published instruction, even if the pressure is low throughout.
Pavers can take pressure, but the joints cannot. ICPI’s range goes up to 4,000 psi, far above anything allowed on brick. The risk on a paver patio is not the paver face, it is the joint sand washing out, which is why ICPI stresses a wide spray at a low angle.
Pro tip: Before anyone washes your house, ask what they will use on each surface: roof, brick, siding, driveway, patio. Then check the answer against the table above. A good answer changes by surface. A single pressure setting and a single mix for everything is the answer to walk away from.
Which Method Does a Typical Garner House Need?
Most Garner houses need low-pressure cleaning on the roof and walls and real pressure only on the flatwork, which means both methods in one visit. Here is how the published rules map onto a common Garner lot, from the older brick ranches around Historic Downtown Garner to the newer mixed-material builds in South Creek and Bingham Station.
The roof. ARMA and GAF agree: a bleach solution, dwell time and a low-pressure rinse, never a pressure washer. That is what roof cleaning means on an asphalt shingle roof, and it is why the black streaks on a north slope under pine canopy are treated with a solution rather than force. What the streaks are, and why they come back, is covered in our post on black streaks on roof shingles.
The brick. Garner’s brick fronts and brick skirts sit in red clay splash range, and BIA’s limits are clear: saturate first, rinse at 100 to 400 psi, stay well under 800. Our brick-only guide, how to clean a brick house exterior, covers mortar joints and the white efflorescence salts that show up on Garner brick after a wet spell.
The fiber cement and the vinyl. Many newer homes in the NC-42 and White Oak Road subdivisions carry fiber cement on the front and vinyl on the sides and back. Both get low pressure, but by James Hardie’s own page the fiber cement also gets no bleach, so the walls may need two different treatments on the same wash day. That is the practical meaning of soft washing on a house wash: matching the solution as well as the pressure. Our guide to whether you can pressure wash Hardie board siding covers the fiber cement rules in full.
The driveway and the patio. A poured driveway carrying red clay and tire marks is where pressure, run through a surface cleaner, earns its place in driveway and concrete cleaning. A paver patio gets pressure too, but with ICPI’s wide, low spray and an eye on the joints.
If you are planning the whole property at once, the Garner pressure washing cost guide explains how bundling surfaces into one visit affects the quote.
Frequently Asked Questions
Is soft washing just pressure washing with the pressure turned down?
No. Turning the pressure down removes the force but leaves you with water alone, and water alone does not kill algae or mildew. Soft washing swaps force for a cleaning solution and dwell time, which is exactly the method ARMA and GAF describe for shingle roofs: apply, wait up to 20 minutes, then rinse at low pressure.
Can you pressure wash brick?
At low pressure, yes, within BIA’s limits: 100 to 400 psi for rinsing, a 25 to 50 degree fan tip, and at least 12 inches from the wall. BIA calls anything over 800 psi “not appropriate for brick.” Older soft brick near Historic Downtown Garner deserves a trial patch first, which BIA also recommends. The full method is in our brick cleaning guide.
Does soft washing use bleach on every surface?
It should not. Bleach solutions are the published method for asphalt shingles, but James Hardie tells owners not to use bleach or acid on its fiber cement siding. A proper soft wash matches the solution to the surface, which on a mixed-material Garner house can mean more than one mix in a single visit.
Does pressure washing a roof void the shingle warranty?
The manufacturers’ published instruction is simply not to do it: ARMA says never use a pressure washer, and GAF’s bulletin says no power washing. Whether a particular warranty is affected depends on its own terms, so read yours. The safer course is to follow the published method, which is what a proper roof cleaning does. Our post on whether roof cleaning voids a shingle warranty goes through what the warranties actually say.
Is the soft wash solution safe for my plants?
The roof and brick sources all tell you to protect landscaping, so it is safe only when it is handled carefully. Pre-wetting, covering and rinsing beds are the standard steps, and our guide to whether soft washing is safe for plants and pets goes through them one by one.
How do I find the cleaning rule for my own siding?
Start with the manufacturer’s name, which is often on the original paperwork, a leftover piece in the garage, or the back of a loose panel. Their care page will say what pressure and cleaners they allow. If you are not sure what you have, send a photo through the contact page and we can tell you which method it needs before quoting.
Soft Washing or Pressure Washing: Get the Right One on Every Surface
The honest answer to soft washing vs pressure washing is that the surface decides, and the people who made the surface have already written the rule down. Shingles get a solution and a low-pressure rinse, brick stays under BIA’s limits, fiber cement gets low pressure and no bleach, and concrete is where real pressure belongs.
We provide low-pressure house and roof washing and surface-cleaner concrete work across Garner, Clayton, South Raleigh, Willow Spring and Fuquay-Varina, with free quotes and up-front pricing. See the pressure washing cost guide for how pricing works, or request a free quote and tell us what your house is made of.
