If a Contractor Shows Up With Colored Tips to Wash Your House, Send Them Away
This is not a subtle point. It is the single most useful thing we can tell a Spokane homeowner who is about to hire someone to wash the exterior of their house.
The colored tips that come standard with almost every consumer and contractor grade pressure washer are not designed for house washing. They are designed to maximize pressure output at different spray angles. Each color represents a different degree of fan. Zero degree is a direct stream that will cut through almost anything in front of it. Twenty-five degree is what most contractors reach for when they want to move fast. Forty degree is slightly gentler but still not appropriate for vinyl siding, painted wood, stucco, or Hardie plank.
When a contractor uses those tips on your siding here is what actually happens.
What High Pressure Does to Your Home's Exterior
High pressure water forced against siding does not just clean the surface. It finds every gap, every unsealed edge, every penetration point and pushes water behind the siding and into the wall cavity. Mold and mildew growing inside your walls from water intrusion is not a cosmetic problem. It is a health problem and a structural problem and it is expensive to remediate.
On vinyl siding specifically high pressure interacts with oxidation in ways that leave permanent marks. The oxidation layer on older vinyl is not uniform. When a pressure washer tip moves across an oxidized surface at high pressure it strips the oxidation unevenly leaving streaks and marks in every direction that you cannot wash out because the washing is what caused them. We call these Zorro marks. We have been called in to assess them on houses that were cleaned by someone with the wrong equipment. In most cases the only fix is paint.
High pressure also strips paint from wood siding, lifts shingle edges on roofs near the roofline, and damages the finish on composite materials like Hardie plank that are specifically designed to be cleaned at low pressure.
The damage is not always visible immediately. Sometimes it shows up weeks later when the water that got behind the siding has had time to cause problems. By then the contractor is long gone.
What Soft Washing Actually Is
Soft washing is not a marketing term. It is a specific method with specific equipment and specific chemistry that produces results high pressure cannot match on the surfaces it is actually designed for.
Here is how it works in practice.
Instead of the colored tips that come with the pressure washer we use specialized low pressure tips that drop the output to a range where the spray would not hurt your hand if you put it in front of the nozzle. The pressure is that low. What does the cleaning work is not mechanical force at all. It is chemistry.
We downstream a house wash mix through the machine that treats algae, mold, mildew, and organic growth at the source. The chemistry is applied evenly across the siding, allowed to dwell for a set period, and then rinsed off at low pressure. The organic growth dies and releases from the surface rather than being blasted off the top while the root structure stays attached and grows back within a season.
For areas with significant algae or mold buildup we use a dedicated twelve volt pump that applies a more concentrated mix at even lower pressure than the downstream setup. These pumps release eight to sixteen gallons per minute at pressure gentle enough that we can safely clean up to three stories from the ground without risking water intrusion, paint stripping, or the Zorro marks that come from the wrong tip on the wrong surface.
Why Window Cleaning Companies Often Get This Wrong
A lot of window cleaning companies in Spokane offer house washing as an add-on service. That is not inherently a problem. The problem is when a company adds house washing to their service list without adding the knowledge and equipment that house washing actually requires.
Window cleaning and house washing use completely different tools, completely different chemistry, and completely different techniques. A window cleaner who grabs the pressure washer and the colored tips because a customer asked for a house wash is not doing house washing. They are doing something faster and cheaper that produces results ranging from adequate to damaging depending on the specific surface and what they hit with the wrong tip.
We came out of the window cleaning industry. We know this from the inside. The companies that do both well have invested in understanding both. The ones that add house washing as an afterthought treat it like an afterthought.
How to Tell the Difference Before Anyone Starts Work
You do not have to wait until the contractor shows up with the wrong tips. Ask before they arrive.
What method do you use for house washing? If the answer is pressure washing without any mention of soft washing or low pressure application that is worth following up on.
What tips do you use on vinyl siding? If they cannot answer this question specifically or if they mention color coded tips without explaining the PSI output those tips produce you have learned something useful.
Do you downstream your cleaning chemistry or do you apply it separately? Downstreaming is the standard soft washing method. A contractor who does not know what downstreaming is has not invested in learning the process.
If you are not sure after talking to them look at the equipment when they arrive. Specialized low pressure soft wash tips are visually distinct from standard colored tips. A soft wash setup has a separate chemical tank or downstream injector built into the system. If they pull up with a gas pressure washer and a set of standard tips and nothing else you already know what you are getting.
What Soft Washing Does That High Pressure Cannot
The results last longer. This is the thing most homeowners do not realize until they have had both done.
High pressure washing removes the visible layer of algae and mildew from a surface. The root structure stays attached to the siding. Within a season the growth comes back because it was never killed. The house needs to be washed again.
Soft washing kills the organic growth at the root with chemistry. The results last significantly longer because there is nothing alive left to regrow. Most Spokane homes soft washed properly stay clean for one to two years before needing another treatment.
Soft washing is also the only method safe for every surface on your home’s exterior. Vinyl siding, wood siding, stucco, Hardie plank, painted surfaces, trim, fascia, soffits. All of them respond well to low pressure chemistry and respond poorly to high pressure force.
Ready to have your Spokane home washed the right way? See our full house washing service page for pricing and what to expect, or call or text Kris directly at 509-464-9461 for a same day quote.