Professional pressure washing companies use six core chemicals on a daily basis: sodium hypochlorite (industrial-grade bleach) as the primary cleaning agent, surfactants to increase dwell time, industrial degreasers for oil and grease, oxalic acid for rust removal, bleach neutralizer to protect plants and equipment, and gutter stripe remover for tiger stripes. The chemical you buy at the store is not the same concentration the pros use. Below is the full breakdown of each product, when to use it, what surfaces it works on, what to avoid, and the three professional application methods — downstreaming, batch mixing, and metering.
Mike walks through every chemical his company uses and explains the ratios, application methods, and safety considerations.
| Chemical | What It Does | Used On | Required? |
|---|---|---|---|
| Sodium Hypochlorite (SH) | Kills mold, mildew, algae, organic growth | Houses, roofs, fences, concrete | Yes — primary chemical |
| Surfactant | Increases dwell time, traps dirt | All surfaces (essential on roofs) | Highly recommended |
| Industrial Degreaser | Attacks oil, grease, heavy stains | Concrete, driveways, commercial | As needed |
| Oxalic Acid | Removes rust stains | Concrete, siding, brick | As needed |
| Bleach Neutralizer | Protects plants and equipment | Landscaping, gear, trailers | Strongly recommended |
| Gutter Stripe Remover | Removes tiger stripes from gutters | Aluminum gutters | Add-on service |
Sodium hypochlorite is the backbone of professional pressure washing. It is the same active ingredient found in household bleach — but the industrial-grade SH that professionals buy is substantially stronger. Store-bought bleach runs 3–6% concentration. Professional SH is 10–12.5% and is purchased in bulk from chemical suppliers or pressure washing supply houses. It is not typically available on retail shelves.
SH does three critical things: it disinfects surfaces, removes stains, and kills organic material including mold, mildew, algae, and lichen. It is used on houses, roofs, fences, concrete, brick, stucco, vinyl, wood, and virtually every exterior surface that needs cleaning.
Tracking which chemical mix you used on each job — and what the customer was charged — becomes important fast. A CRM built for pressure washing businesses lets you log job details, chemical usage, and pricing so you are not guessing on repeat visits.
A surfactant is mixed with sodium hypochlorite to increase the chemical’s dwell time on surfaces. Without surfactant, the SH solution runs off the wall quickly. With it, the chemical clings to the surface long enough to do its work. Surfactant also helps trap dirt and pollutants in the water, making the rinse more effective.
Most operators always use surfactant on roof cleaning jobs. For house washes, it is a personal choice — some use it every time, some skip it. Mike’s company does not use surfactant on standard house washes but always uses it on roofs.
A professional degreaser attacks oil stains, grease, and other heavy contamination through an aggressive chemical reaction. This is the product you reach for on restaurant parking lots, gas station pads, commercial kitchen areas, and residential driveways with stubborn oil spots.
Mike’s company uses Big Dog (from LH in Savannah) and Dynamite Degreaser (from Southeast Softwash). Multiple commercial-grade options exist from pressure washing suppliers.
Oxalic acid is the active ingredient in most commercial rust removers designed for exterior surfaces. Rust stains on concrete and siding come from several sources: fertilizer containing iron, iron leaching from the ground, and well water with high mineral content — especially when an unfiltered well feeds an irrigation system that sprays across the concrete and house.
A good oxalic acid product will treat these stains effectively. Apply, allow dwell time, and rinse. Multiple applications may be needed for severe staining. Several name-brand products contain oxalic acid as the primary active ingredient — check the label at your pressure washing supplier.
A bleach neutralizer is applied to plants, grass, and landscaping as an added insurance policy against chemical damage. It does not replace the need to water vegetation thoroughly before, during, and after the cleaning process — that is non-negotiable. The neutralizer is extra protection layered on top of proper watering procedure.
Beyond landscaping, bleach neutralizer is valuable for equipment maintenance. Pressure washing is a corrosive environment — water and SH destroy metal over time. Spraying down your trailer, hose reels, and fittings with neutralizer after each job extends the life of your equipment significantly.
Those ugly black vertical stripes running down aluminum gutters are called tiger stripes. They are not surface dirt — they are the result of a chemical reaction between asphalt residue from roof shingles and the anodized aluminum in the gutters. A standard house wash will not remove them. They require a specifically formulated gutter stripe remover product.
Mike’s company uses Gutter Guard. Application, dilution, and method vary by stain severity — sometimes a spray-and-rinse is sufficient, other times you need light agitation with a brush. Every stain is different.
You never apply sodium hypochlorite at full strength. Here is how professionals dilute and deliver it.
A downstream injector sits after the pump and draws chemical from a separate tank, mixing it into the water stream at a fixed ratio (typically 10:1 to 20:1). This is the most common method for house washing — it is simple, consistent, and keeps chemicals out of the pump. Most entry-level operators start here.
Pre-mix the SH, water, and surfactant in a tank at the exact target ratio before application. This gives you precise control over concentration. Common for roof cleaning where a stronger mix is needed and consistent application matters. Requires understanding ratios and doing the math before each job.
An adjustable metering valve controls the chemical-to-water ratio in real time. Allows you to change concentration on the fly for different surfaces or stain levels. More expensive and complex to set up but offers maximum flexibility for experienced operators running multiple service types.
As your operation grows and you are managing multiple jobs per day, automated scheduling keeps your day organized while automated review requests build your Google reviews without any manual follow-up — which is the last thing you want to think about after spending all day around SH.
Professional pressure washers use six core chemicals: sodium hypochlorite (industrial-grade bleach) as the primary cleaning agent, surfactants for dwell time, industrial degreasers for oil and grease, oxalic acid for rust removal, bleach neutralizer for plant and equipment protection, and gutter stripe remover for tiger stripes on aluminum gutters.
Sodium hypochlorite is the active ingredient in bleach, but professional SH is substantially stronger than store-bought versions. Industrial SH runs 10–12.5% concentration compared to 3–6% in household bleach. It is purchased in bulk from chemical suppliers and is not available on retail shelves.
No. Never use dish detergent like Dawn when pressure washing with sodium hypochlorite. Dish soap is not formulated to work with bleach. If you need a store-bought option, use a laundry detergent — it is specifically formulated for bleach compatibility. Professional surfactants like Southeast Softwash Southern Drawl are the best option.
A surfactant is a soap mixed with sodium hypochlorite that helps the chemical cling to surfaces longer, increasing dwell time and cleaning effectiveness. It also traps dirt in the water for easier rinsing. Surfactants are essential for roof cleaning and optional for house washing.
Use oxalic acid, the active ingredient in most commercial concrete rust removers. Rust stains are commonly caused by fertilizer, iron leaching from the ground, or mineral-heavy well water sprayed through irrigation systems. Apply the product, allow it to dwell, then rinse. Multiple applications may be needed.
Tiger stripes on gutters are caused by a chemical reaction between asphalt residue from roof shingles and anodized aluminum gutters. Rainwater carries the residue down and it bonds with the metal. A standard house wash will not remove them — you need a specifically formulated gutter stripe remover.
Strongly recommended. A bleach neutralizer is extra insurance to protect plants and landscaping from SH damage. It does not replace thorough watering before, during, and after the wash — it is added protection on top. It also extends equipment life when sprayed on trailers, fittings, and hose reels.
Downstreaming uses an injector placed after the pump that draws chemical from a separate container and mixes it into the water stream at a fixed ratio (typically 10:1 to 20:1). It is the most common application method for house washing because it is simple, consistent, and keeps chemicals out of the pump.
Pressure washing uses high water pressure to mechanically clean hard surfaces like concrete and brick. Soft washing uses low pressure combined with chemical solutions — primarily sodium hypochlorite and surfactant — to clean delicate surfaces like vinyl siding, stucco, and roofs. Most professional companies offer both.
Water all plants, grass, and landscaping thoroughly before applying chemicals. Continue watering during the process. Rinse all vegetation again after the wash. Apply bleach neutralizer to all plant areas as added insurance. This multi-step approach minimizes the risk of chemical damage.
25-Year Pressure Washing Veteran · QuoteIQ Co-Founder · 580K+ YouTube Subscribers
Mike Vidan has operated a pressure washing business in Savannah, Georgia for over two decades — from a one-truck solo operation to a seven-figure, multi-truck company. He has personally used every chemical on this list across thousands of residential and commercial jobs. He co-founded QuoteIQ, a CRM for home service contractors with 40,000+ daily users, and teaches contractors how to start, price, and scale through his YouTube channel and training programs.
Mike offers field-tested training for pressure washing and home service business owners — including detailed chemical application, soft wash systems, and business scaling strategies.
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