You need to ensure that you read the owner’s manual for the pressure washer that you are using before taking on this kind of project.
Make sure that if the surface you are cleaning is in a garage/other enclosed areas, it needs to be properly ventilated at all times.
What you need to know about cleaning concrete with a Pressure Washer
Cleaning concrete with a pressure washer is easy and quick. Pressure washing the concrete will remove dirt, mold, algae, or any other unwanted residue that may be on the surface of your concrete.
However, precautions need to be taken to else you could end up causing damage to your concrete surface. Something as simple as the wrong nozzle can be devastating.
How to Clean Concrete with a Pressure Washer
You may or may not think it’s as simple as hooking up the pressure washing and spraying everything that you can spray, however you should proceed with caution before cleaning anything with a washer.
Here's what we recommend:
- Remove all loose items from the area to a safe place.
- Sweep the area with a brush if there is lots of debris.
- Apply any cleaning solution you're going to be using and allow it to soak of up-to 15 minutes. Keep it wet if you're working on a hot day.
- Connect you pressure washer to water supply using your garden hose
- Attach your wand. Ensure it is the wand supplied with your machine and that it is suitable for the PSI you're going to be using
- Start spraying with 25 degree green nozzle. Use a gentle back and forth sweeping movement with each run overlapping. You want a wide fan that covers as much area as possible without taking away from the power of the water stream.
Can a Pressure Washer Damage Concrete?
YES! Having too much pressure when the water hits the surface is one of the most common ways that a pressure washer damages concrete. Believe it or not, it happens quite often, especially when one tries to take the project on without educating themselves on what all is involved.
As far as knowing when your concrete was damaged while power washing it, you will be able to notice etching or other forms of concrete damage. Keep in mind that just because it looks like your concrete was damaged and you didn’t notice it before, it could have been damaged previously, and removing the dirt/grime helped reveal it to the point where it was noticeable.
Aside from too much pressure, concrete is known to become damaged while pressure washing when the tip of the wand gets too close or if it was cleaned too often (it is only necessary to clean it once per year, but some homeowners have done it monthly or even more frequently than that). A newly installed concrete surface also needs to be left alone and not power washed for at least a year.
Tips for Cleaning Concrete with a Pressure Washer
It is always nice to know some tricks to get things done easier and quicker when taking on any kind of project, especially when it comes to making your concrete look it's best.
Here are our top tips for cleaning concrete using a high-pressure power washer.
What Pressure Washer Nozzle Should You Use to Clean Concrete?
Different nozzles should be used for different stages of the concrete cleaning process, so make sure to take note of which ones you need and when to use them.
This will help ensure you save time and do things correctly, as we have already tested out every pressure washer nozzle to ensure our recommendations are completely accurate while delivering our readers with the best solution.
In the beginning, when you are applying the concrete detergent (or degreaser) you can use a 65-degree tip. For those who are unsure about what the size means exactly, the higher the number is the bigger width of the fan that is produced by the stream of water. Check out our pressure washer tip guide for more info.
For the actual cleaning process, use a 25-degree as it seems to be the quickest and most effective pressure washer tip for this stage. If you find yourself dealing with stubborn buildups/stains, you can switch it out with a 15-degree nozzle to make things easy.
What PSI Is Best When Cleaning Concrete with a Pressure Washer?
Many home improvement experts have tested out different pressure washers to see exactly which one works the best on concrete. From our studies, it seems that the best results when it comes to using a pressure washer to clean concrete can be seen from one that is 3,000-3,100 PSI.
The less powerful pressure washers do have the ability to provide you with what you need for general cleaning but expect it to take a bit longer on concrete that has been subject to more intense staining or dirt buildup.
Is It Safe to Clean Concrete with a Pressure Washer?
YES, however, just as it is with most things if you have the right equipment and embrace the right process you can clean concrete with a pressure washer safely.
If pressure washing in an enclosed area always make sure there is plenty of ventilation!