Soap or Detergent? Which is the best for my pressure washer?
With so many soaps and detergents, knowing exactly which one to use in your pressure washer can be a challenge.
It’s a challenge because there is no one size fits all answer, are you washing a car? then you’ll want a soap/detergent that best suits that task, what about cleaning decking? house siding? algae building up in your driveway?
Each of these tasks will most likely result in a different soap or detergent.
Then there’s the question of soap or detergent? Does it matter? Will one work better than the other in my pressure washer?
What about pressure washers with Upstream versus Downstream injectors? Will that affect which soap or detergent to buy?
If your head is spinning, don’t worry i’ll answer all and more below, by the end of this article you’ll be an expert in which soap or detergent to use in your pressure washer for the tasks that you are looking to tackle.
What Is the Difference Between Soaps and Detergents?
- What Is the Difference Between Soaps and Detergents?
- Soap and Hard Water May Create Unwanted Buildup
- Soaps Includes Specific Chemicals for Different Applications
- The Difference Between Consumer and Commercial Soaps
- Using DIY Soap Mixtures for Your Pressure Washer
- Upstream Delivery Versus Downstream Injectors
- How to Choose the Right Soap for Your Cleaning Task
- Choosing the Top Pressure Washer Soap for Siding
- The Most Recommended Cleaner for Decks and Fences
- The Most Effective Power Wash Soap for Concrete
- The Top Pressure Washer Soap for Degreasing
- The Best-Selling Soap for Cleaning Motor Vehicles
- The Most Used Multipurpose Power Washer Soap
- In closing
When you start shopping around for soaps, one of the first things you’ll notice is that some products are labeled as soaps and others as detergents.
The label is not just part of the marketing.
Detergents contain synthetic chemicals for specific uses, such as killing mold or helping to dissolve grease.
The “synthetic chemicals are often harsher” compared to the ingredients commonly found in soaps.
Soaps are detergents that contain natural ingredients such as oils and fats. These substances are combined with an alkaline solution using a cold or hot process.
With the cold process, the alkaline solution is cooled before combining it with the oils and fats.
The ingredients are mixed just above room temperature until they thicken. With the hot process, the alkaline solution and the oils are combined and then heated.
Due to the natural ingredients, soaps are biodegradable. You can wash the runoff into the gutters. You’re also less likely to need to protect plant life from the soap while many detergents can kill grass, plants, and vegetables.
Soap and Hard Water May Create Unwanted Buildup
The only drawback to soap is that it shouldn’t be used with hard water.
The hard water contains calcium and magnesium “particles that react with the soap to create scum”. The resulting scum clings to surfaces and is difficult to clean.
With a chemical detergent, the water doesn’t matter.
The hard water does not have the same reaction to the chemicals found in detergents. However, the detergents have their own drawbacks.
Detergents should not be run off into the ground or the sewer system. Unlike soap, the chemicals in detergent take a long time to break down.
The bottom line is that soaps are meant for dealing with dirt and grime while detergents are often made for sanitizing and disinfecting. However, there also detergents designed for specific cleaning jobs, such as removing grease or oil.
Soaps Includes Specific Chemicals for Different Applications
You may need to use a specific type of soap based on the surface that you’re cleaning.
Most general soaps are designed to help remove dirt and debris. There are also sanitizing soaps that help kill bacteria and disinfectants that help kill all organisms. You can even find soaps designed for rust removal.
The most commonly used chemicals and ingredients in soaps and detergents include:
- Citric acid
- Oxalic acid
- Sodium hydroxide
- Sodium hypochlorite
Each of these ingredients has its own use. For example, oxalic acid is often used for helping to eliminate rust while citric acid is commonly used for cleaning wood surfaces.
Using a cleaner with oxalic acid may harm a wooden deck while the citric acid may not work well on metal surfaces.
Ammonia is commonly used for cleaning stainless steel and glass. However, it may also be harmful to the environment and your plants when used outdoors.
The same is true with bleach and petroleum.
The Difference Between Consumer and Commercial Soaps
The main difference between consumer and commercial soaps or detergents is the concentration.
Consumer products often come pre-mixed while professionals tend to buy concentrated formulas in bulk.
I know that you still need to mix most consumer soaps with water. However, the commercial soaps require even more water to get the right concentration. They are also often sold in large tubs, barrels, or containers.
Unless you plan on washing the house of every friend, family member, and neighbor, you shouldn’t need to buy bulk commercial soaps for household cleaning projects.
There are also many consumer products that feature commercial-grade formulas. This eliminates the need to buy commercial concentrate soaps and detergents for general household cleaning.
Using DIY Soap Mixtures for Your Pressure Washer
To save money, it can be tempting to prepare your own soap mixture using common household cleaners. Vinegar solutions and bleach are the two items that are most often recommended.
I strongly advise against “using bleach in your pressure washer” unless you purchase a detergent that includes bleach as an ingredient.
Before researching the different types of soaps, I used bleach to help kill mold growth on my siding. While it worked great, I eventually noticed that it corroded the nozzle and I had to buy a new washer. Besides destroying my washer, “bleach may also be bad for the environment”.
Vinegar is one of the few household ingredients that you may use with your pressure washer.
Use three parts vinegar to seven parts water to create a potent solution for killing mildew and mold.
The vinegar is also safe for your plants so you don’t need to worry about covering your garden before spraying.
For almost every other type of cleaning project, I suggest that you stick with soaps and detergents designed specifically for pressure washers.
You can easily find a soap with the right combination of ingredients for the surfaces that you want to clean without worrying about damaging your power washer.
Upstream Delivery Versus Downstream Injectors
With pressure washers, there are two primary ways to add soaps or detergents — upstream and downstream delivery systems.
With upstream, the “chemicals are added before reaching the pump” while downstream injectors add the chemicals after the pump.
Which system should you use? This is a hot topic in the pressure washing industry. Some people swear that upstream is the only way to go while others claim that downstream is the best solution.
With an upstream delivery system, the chemicals pass through several components including the pump.
The use of an upstream delivery system allows for more pressure and slightly higher temperatures. However, there are a couple of drawbacks.
As the chemicals need to pass through the pump, the abrasiveness of the chemicals may eventually damage the components. As I stated, using household bleach can quickly damage these parts.
With a downstream injector, chemicals are drawn into the system and do not run through the pump.
This allows you to use chemicals that may be too harsh for the pump. Some people also find downstream injectors easier to use.
How to Choose the Right Soap for Your Cleaning Task
When choosing a cleaner for your pressure washer, you need to consider a few details, including:
- Soap or detergent
- The delivery system
- The type of surface
- The setting
First, consider the type of surface and the setting. If you’re cleaning a vehicle in your driveway, you likely want a soap for your pressure washer.
The soap can run off into the gutter and is likely to be more effective at removing dirt and grime.
If you’re cleaning siding, you may want soap or detergent. For general cleaning, a soap may offer the right option as the excess water and chemicals may not hurt surrounding plant life.
When you need to blast mold and mildew on the side of the house, a detergent may be needed. Keep in mind that you may need to cover flower or garden beds and try to minimize runoff into the ground and sewer.
The type of solution you choose may also depend on the delivery system.
If you use a downstream injector, you have more options. With an upstream delivery system, harsh chemicals may damage the internal components such as the seals on the pump.
You should also look at the intended use of the product.
Most soaps and detergents are designed for cleaning specific surfaces or tackling certain issues, such as removing buildup from siding or safely cleaning a wood deck.
Another consideration is whether the soap uses biodegradable ingredients. A biodegradable soap is suitable for use outdoors and may not cause harm to the environment. These products are also less likely to damage your plants and grass or pose a health risk to your pets.
Choosing the Top Pressure Washer Soap for Siding
When cleaning the siding, I prefer to use a product that is safe for plants and my pets. It is a lot easier to deal with a biodegradable solution. However, you also need something that is strong enough to help remove grime and buildup from the siding.
If you want to safely clean your siding, the “Krud Kutter HS01 Green Pressure Washer Concentrate House and Siding Cleaner is an effective choice.
It is biodegradable and “contains ingredients that may help get rid of mold”, fungus, and algae. You may even use this soap on wood decks and fences.
This soap is sold in one-gallon jugs. With a 1:10 soap to water ratio, you should get enough coverage for cleaning up to 2000 square feet. For a typical residential house, this should offer more than enough soap for at least one good cleaning.
The Most Recommended Cleaner for Decks and Fences
Krud Kutter is a name that you should recognize as they produce some of the most recommended pressure washer soaps and detergents, including the Krud Kutter DF01 Deck and Fence Concentrate.
The “Deck and Fence soap may get rid of the algae”, mold, and mildew growing on your wooden decks or fences. It does not contain any ammonia or bleach and it is biodegradable.
You simply wash the wooden surface and then spray the solution from your pressure washer.
Of course, you may also use the Krud Kutter HS01 Green Pressure Washer Concentrate, which is suitable for most of the exterior of your home including the decks, fences, and siding.
The Most Effective Power Wash Soap for Concrete
For cleaning concrete, you want a soap that can remove grime without destroying the concrete. Simple Green 18202 Concrete and Driveway Cleaner has a formula that may help “get rid of the oil stains on your driveway” without degrading the surface.
The Simple Green cleaner comes in a one-gallon container, which should offer enough soap for about a dozen washes. Of course, the coverage depends on the size of your driveway and concrete patio.
The Top Pressure Washer Soap for Degreasing
Degreasing soaps and detergents often require stronger chemicals to help remove the grease. However, there are non-corrosive degreasers.
For example, the Simple Green 13421 Pro HD Heavy Duty Cleaner only includes “non-toxic and non-corrosive ingredients”, making it safe for use on metal surfaces. While it is non-corrosive, it is still effective at general cleaning and degreasing.
This soap may remove stains and eliminate tough grease and buildup from a variety of surfaces.
You can use this cleaner for cleaning industrial equipment, commercial kitchens, vehicles, floors, and walls.
If you are worried about the abrasiveness of the Simple Green Heavy-Duty Cleaner, Krud Kutter offers a commercial-strength degreasing soap.
The Krud Kutter KK012 Original Concentrated Cleaner Degreaser may be applied directly to surfaces and “works on a variety of surfaces”. However, it does produce a mild odor.
The Best-Selling Soap for Cleaning Motor Vehicles
Whether you want to wash your car, boat, or RV, you should find a soap designed specifically for vehicles. The chemicals found in some cleaners may dull the finish on the vehicle or completely remove the wax.
Karcher Car Wash & Wax Soap for Pressure Washers is made specifically for cleaning vehicles. It is a biodegradable product that “does not leave any residue after washing”. You get a complete wash and wax in a single product and it is safe for use on any vehicle, including a boat or motorcycle.
The soap is often sold in one-gallon containers and a 1:5 soap to water ratio is suggested, which means that you get up to five gallons of solution per bottle.
The Most Used Multipurpose Power Washer Soap
Along with soaps for specific uses, there are multipurpose soaps that can be used on a variety of surfaces.
The variety of surfaces that it is designed to work on allows you to use this cleaner on your siding, driveway, decks, and fences without switching between different soaps.
Basically, you are getting a product that can cover the entire exterior of your property from the vinyl or aluminum siding to the wood decking and concrete surfaces.
The Krud Kutter Purple Multi-Purpose cleaner uses a water-based solution without any ammonia, bleach, or petroleum. You can use it outdoors without risk to your plants or yard.
Hopefully I’ve given you enough information to know exactly what to purchase for your pressure washer and the job you are looking to complete.
If I haven’t, please drop a comment or head to the contact us section and reach out, i’ll do my best to help guide your choice.
Last update on 2019-01-17 / Affiliate links / Images from Amazon Product Advertising API