Spring cleaning doesn’t only happen in the spring. Perhaps you’re preparing to sell your home. Maybe you have your own pressure washing business or are just meticulous about your keeping your car clean.
Whatever the reason, the time has come to break out the pressure washer. Using a good detergent or soap with your pressure washer will help you get the job done right.
Your pressure washer may have a detergent tank attached that delivers the cleaning solution through a hose to combine with the water to spray onto the surface you’re cleaning. Detergent or soap is an effective additive when you’re battling stains, algae, and dirt.
You may be wondering what the difference is between detergent and soap. This typically requires some knowledge of chemistry, but we’ll keep it simple.
Detergent is a stronger man-made solution designed to address specific cleaning needs. Soap is a derivative of natural ingredients, keeping it environmentally friendly. Here, we’ll walk you through our reviews for best pressure washer detergents and soaps.
|Model||Price||Sizes Available||Editor Rating|
|Karcher Multi-Purpose Detergent|
|1 gallon, 1 quart||4.8/5|
|Simple Green Industrial SMP11001||1 gallon||4.5/5|
|Karcher Car Wash & Wax Soap||1 gallon, 1 quart||4.4/5|
|Sun Joe SPX-HDC1G||1 gallon||4.2/5|
|Simple Green Pro HD||1 to 5 gallons||4.1/5|
The Karcher Multi-Purpose Cleaning Detergent Soap kicks the list off as our best overall choice. This cleaning solution is formulated specifically to use with pressure washers and has a 1:20 concentrate-to-water ratio. It’s a formula for outdoor surfaces but is biodegradable and thus not harmful to plants. Available in pint or gallon size, this concentrate will produce many gallons of ready-to-use cleaner.
This solution is alkaline, so it won’t strip wax or sealants. Some users have noted, however, that it leaves streaks on windows. If used on your house, prepare for follow-up cleaning on windows and doors. You may also want to forgo this choice if you intend to use it to wash your car, as it may leave spots or residue behind.
Simple Green Industrial SMP11001 is from a brand that’s been in the cleaning game for over 40 years. This runner-up choice is a biodegradable option designed to clean hard surfaces and has a 1:64 concentrate-to-water ratio. It’s Green Seal GS-37 certified and LEED compliant — GS-73 is an eco-labeling organization, and LEED is a certification for environmentally sound buildings. Both encourage sustainability and environmental conscientiousness, so this cleaner is a purchase you can feel good about.
While this cleaner will work its magic on grease, it’s not recommended for windows or glass. It’s labeled fragrance-free, but some users have noted an unexpected aroma during use, which is what caused it to drop into our number-two spot.
Karcher Car Wash & Wax Soap is made specifically to use in a pressure washer to wash your car. It has a 1:20 concentrate-to-water ratio and is biodegradable. This cleaner is recognized highly for leaving a car super shiny, but you can also use this on any truck, boat, motorcycle, or RV.
It produces good sudsy action while being thin enough not to clog your pressure washer. As a bonus, it’s a wash and a wax combined and doesn’t leave a residue behind. It’s slightly pricey, but if you want to save yourself the time of going to a car wash, it may be money well spent.
Sun Joe SPX-HD1G House and Deck All-Purpose Cleaner is another versatile, eco-friendly option that’s safe enough to use on vehicles, homes, decks, and pools.
As with all eco-friendly cleaners, it doesn’t contain harsh chemicals, which makes it safe for landscaping and waterways. However, the cleaning result may be disappointing if you’re expecting it to deliver the same results as a detergent or bleach. Still, you can feel good about not damaging an heirloom rose bush or contaminating nearby water, though we don’t recommend pressure washing your lawn. This brand takes customer service seriously and offers a satisfaction guarantee.
See the best: Electric water pressure washers
Simple Green Pro HD Heavy Duty Cleaner is a purple-colored professional-grade concentrate that is formulated as a multi-use purpose cleaner and degreaser. It has a wide array of uses and is safe to use on engines and machinery. As a biodegradable, non-caustic agent, this cleaner will not corrode metal, making it ideal for tools, equipment, and automotive grime. It is noted specifically for removing paint overspray.
Many users have indicated that this option is an average conventional cleaner, which is disappointing coming from such a top brand. However, other users have noted that it performs well as a carpet cleaner.
Finishing off our list, Krud Kutter HS01 Green Pressure Washer Concentrate focuses on house and siding cleaning performance. It’s biodegradable and contains an additive, Sporex, to tackle mold, mildew, algae, and moss. With a 1:10 concentrate-to-water ratio, it gently penetrates surfaces to remove dirt and dissolve stains.
Even with the Sporex additive, it may be necessary to use a brush on mold, mildew, or algae to loosen it before pressure washing. It’s this extra work that puts this choice in last place.
What Kind of Soap Should You Use in a Pressure Washer?
A pressure washer is a versatile tool to have in your arsenal of cleaning weapons. Before dumping just any old soap in it, however, you’ll need to match the cleaner to your task. Different tasks may require different cleaners. In the introduction, we touched briefly on the difference between soap and detergent. There are a couple of things we need to explain further, such as hard water and chemicals.
Hard water refers to water containing high levels of minerals. If you live in an area with hard water, which is common, you likely know this already. Hard water doesn’t play nicely with soap because the reaction creates soap scum. Depending on the components in a cleaner, it’s possible to have remaining water spots on your car, for example, after you’ve washed it.
Have you ever pressure washed your house only to discover that the grass and nearby shrubs died? Some cleaners have harsh chemicals that can damage landscaping or discolor paint. Using bleach in a pressure washer is not a great idea either. Depending on the solution injector system, bleach can damage the interior parts of your machine. If you’ve used a detergent to wash your car, it can run down the driveway, into the street, and then into the storm pipe system, ending up in the waterways.
Before you decide on the soap or detergent, you’ll need to consider a few details of your project, such as purpose and the machine injector system.
To wash your vehicle, you’ll want a cleaning agent that won’t strip the paint, damage the metal, or cause harm if it enters a storm drain. Soap is gentler than detergent and won’t harm the vehicle or anything else.
If you’re washing a concrete drive or walkway, you’ll want to use a soap, preferably a biodegradable one that won’t damage the landscaping. In this instance, pressure may do most of the cleaning. If you need to remove mildew from the house siding, however, you may need a detergent to fight the situation effectively. If there are shrubs or flower beds, you should cover them for protection.
Basically, make sure to choose a cleaner with the intended surface in mind.
If your pressure washer has a downstream injector, the cleaner comes in after the pump, and you’ll have more choices. If your pressure washer has an upstream injector, the cleaner will go through the pump, exposing it to any chemical in the mixture. Harsh chemicals can damage the pump.
When searching for your ideal cleaning additive for pressure washing, there are many choices on the market. Hopefully, our reviews for best pressure washing detergent and soaps can help you narrow down the list. In summary, our top choice is Karcher Multi-Purpose Cleaning Detergent Soap, as it is specially formulated to use on outdoor surfaces at an affordable price. Our runner-up is Simple Green Industrial SMP11001 Clean Building All-Purpose Cleaner Concentrate, which is environmentally friendly. We wish you well on your next cleaning project!
Featured Image By: Karcher Multi-Purpose Detergent Soap, amazon
Hi there! My name is Adam and I write for HealthyHandyman. I have a great passion for writing about everything related to tools, home improvement, and DIY. In my spare time, I'm either fishing, playing the guitar, or spending quality time with my beloved wife. You'll also often find me in my workshop working on some new project!