Pressure washers are extremely useful and versatile when you’re washing things such as wood furniture or cars. Pressure washers can also clean out certain places in your home such your deck, your pool, or even your rooftop.
However, one recurring question that a lot of beginners ask is, ‘how much PSI pressure washer do I need for my washing needs?’
Well, it actually depends.
It would really depend on what things or areas you are cleaning, the current condition of the thing or surface, and how clean you want it.
In this guide, we’ll be getting into detail about how much PSI do I need in pressure washers based on the most common things people wash.
Why You Should Check the PSI Rating of the Pressure Washer?
Before we go to the PSI guide, let’s first talk about why you should check the PSI or GPM in the first place.
Here is the explanation why:
The PSI
Now, PSI stands for pounds per square inch and is a unit of measurement for pressure. That said, the higher the pressure, the stronger the machine.
In a general sense, a stronger machine is good for taking out stickier and more stubborn grime. However, stronger machines may also mean higher risk of damage. This means that if your pressure washer is too strong, you might break or damage whatever you’re trying to wash.
The GPM
Aside from PSI, you may also use GPM as a measure of power. For GPM, the same principle applies. GPM stands for gallons per minute and refer to how much water in gallon is being sprayed out by the minute.
Again, a higher GPM means a stronger machine. In order to avoid damaging whatever you’re trying to wash, you need to select a pressure setting that suits it.
So, the first step in answering the question, “how much PSI pressure washer do I need?”, first consider what you are cleaning.
How Much PSI Do I Need?
The three most common things that people use pressure washers for are cars, wooden furniture, or concrete materials that can be found on the driveways, patios, and the pool floor.
That said, we’ll be discussing the applicable PSI for each of these items:
- Vehicles
First, let’s start with cars. Now cars are not that fragile as compared to glass or some ceramic, so you don’t have to worry too much about damage (unless you aim at the glass windows). What you do have to worry about would be the paint coming off. Not only will it make your vehicle look bad, but it will also encourage rust to spread starting from the bare spot.
For cashing washing, we recommend that you use a PSI of up to 1200 to 2100. Take note though, that some cars scratch more easily than others, so what you can do is start with 1200. If you think it’s too weak, you can increase the pressure a bit more. However, don’t go higher than 2100 PSI. For GPM, you can use a hot water pressure washer with 1.2 to 1.5 GPM.
- Wood Furniture
Next, let’s see how much psi pressure washer do I need for wood. With wood, you will need a stronger pressure washer because you’ll need the strength for spraying away the mold and the mildew.
Unlike cars, you won’t scrape away the finishing of the wood furniture. It is recommended that you get a machine with a pressure level of around 2500 PSI with around 2.0 GPM. That’s good enough to wash away the sticky molds and the stubborn grime that you’ll find even in the inner creaks of your wooden furniture. Also, make sure to spread out the pressure a bit by using 25-degree nozzle.
- Concrete Flooring
Lastly, we have concrete flooring, which can usually be found on your patio or driveway. So, how much psi do I need to pressure wash a driveway?
As concrete is much stronger than wood and your car, you might need a stronger PSI for cleaning. Now, the PSI that you’re going to use for your concrete flooring will really depend on the thickness of the concrete slabs. Usually, concrete flooring would be around 8 inches, so a PSI 3500 to 4000 is good enough.
However, we observe that a PSI of 4500 is ideal for typical concrete flooring. This pressure rate is not too weak and not too strong to clean up the dirt or the grime on the concrete patio or driveway flooring.
Conclusion
With that all said, this answers the question “how much psi pressure washer do I need?”
If you are considering the PSI or GPM of your pressure washer, you must first consider what you’re washing. Next, read our guidelines above to know the ideal pressure for what you need to wash. Always be very careful and conservative when choosing the PSI of your pressure washer.
A pressure washer that’s too weak will not clean properly. A pressure washer that’s too strong, on the other hand, might cause damage. So, you’ll need to find a middle ground. This guide will help you find that middle ground.
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