Dust and grime are no match for the right pressure washer
Your home’s exterior goes through a lot, including dust in the wind, pouring rainstorms, and ice melt all winter long. The good news is that a nice pressure washing can have your dingy siding and deck gleaming like new. For the best results, though, you need to know how to select the best pressure washer for your home.
We’ll run down everything you need to know before purchasing a pressure washer and getting to work.
Choosing the right pressure washer depends on what you plan to use it for. A professional use machine will likely be much more powerful than what the average homeowner needs to wash their deck, and there is a range of commercial products available for DIYers to choose from. Here are some of the important factors to consider when shopping for a pressure washer.
| Type | Consumer | Professional |
|---|---|---|
| PSI | 500 – 4,200 | 1,000 – 7,000 |
| GPM | 1.0 – 4.0 | 1.0 – 10.0 |
| Cleaning Units | 1,500 – 16,000 | 2,400 – 30,000 |
| Water Temperature | Cold | Hot or cold |
While you may be tempted to swipe your card and start spraying down your home, you’ll first need to consider if buying or renting a pressure washer is the right choice for you. If you’re only going to use it a few times a year and don’t have room in your shed for yet another tool, renting a pressure washer or hiring a local pro to pressure wash your home might be best.
However, if you often find yourself with dusty siding, dirty plastic playsets, and a grimy garage floor and feel confident cleaning these up on your own, then buying a pressure washer might be a worthy investment.
If you’ve got your heart set on buying, it’s helpful to understand the differences between power washing and pressure washing.
Though you might think that the terms are pretty much interchangeable, in fact, there’s quite a bit of difference between power washing and pressure washing. Both power washing and pressure washing are good for big jobs that require a lot of cleaning force. Both are also typically done on highly durable exterior surfaces, and both involve very high water pressure.
However, the key difference is that power washing involves heated water, whereas pressure washing doesn’t. Power washing can often achieve better results in less time than pressure washing because the pressurized water's high temperatures help break down organic material more rapidly.
Still, though, you need to use caution when power washing because not all exterior surfaces can withstand the heat. In general, it’s best to reserve power washing for exceptionally tough materials, such as concrete, stone, and masonry.
Additionally, both power washing and pressure washing can be dangerous if you don’t know what you’re doing, so keep this in mind. Always use caution when using these tools.
You’ll want to consider the flow of the water from your pressure washer, measured in gallons per minute (GPM), and the pressure of the washer, measured in pounds per square inch (PSI). The ratio of GPM to PS helps to determine both the machine’s cleaning capacity and its efficiency.
For typical residential use, the GPM will range between 1.0 and 4.0. You typically won’t require a higher GPM rating unless you do regular (and heavy) commercial cleaning work.
Standard machines with a GPM of between 1.0 and 4.0 can easily handle a wide variation in PSI, ranging from as little as 500 to 4,200. So, even with the same GPM rating, you can still have your choice of light, medium, or heavy-duty models.
Choosing the correct GPM or PSI ensures the safety and efficiency of your cleaning efforts. If your GPM or PSI is too high, it can damage the surface you’re cleaning while causing unnecessary water waste. It can also make the job more difficult than it needs to be since a high GPM or PSI makes the pressure washer harder to handle.
If the GPM or PSI is too low, it may not effectively remove dirt and grime. It will also increase the time needed to clean the surface.
Whether you’re choosing a power washer or a pressure washer, the cleaning capacity of your machine will be measured in cleaning units. The machine’s cleaning units (CU) are calculated by multiplying the PSI and the GPM. Thus, a unit with a GPM of 3.0 and a PSI of 3,000 will have 9,000 cleaning units.
For lighter jobs, the ideal CU will range between 1,500 and 16,000. This range is usually best for general residential use.
For medium and heavy jobs, including frequent residential use and commercial use, then the ideal CU will range from 2,400 at the low end to more than 30,000 at the high end.
Choosing between electric and gas pressure washers will be one of your biggest decisions.
Because electric pressure washers generally hold less water, they’re generally best for light work only. Electric pressure washers may be best for vehicle washing and clearing the gunk off your outdoor furniture and the kid’s outdoor toys. However, be sure to do your research and spot test before going in with a pressure washer.
Most electric units have a PSI of between 1,400 and 2,000 and a GPM ranging from 1.1 to 1.75.
On the other hand, gas pressure washers can handle middle, heavy, and extra heavy-duty work. Medium-duty gas washers usually have a PSI of 2,100 to 2,900 and a GPM of 1.8 to 2.6. They’re usually best for washing heavily soiled vehicles or for cleaning patios, decks, fences, boats, and siding. If you’re looking to pressure wash your home primarily, this could be a good option, though be sure to check with your siding and decking manufacturer to make sure pressure washing is a safe cleaning option.
Heavy-duty gas washers have a PSI ranging from 3,000 to 3,300 and a GPM of 2.3 to 2.8. With these beasts, you can not only do some heavy vehicle washing, but you can also clear off patios, siding, decks, fences, and boats that have a bit of caked-on dirt and grime. Extra heavy-duty gas washers have a PSI between 3,400 and 4,000 and a GPM of up to 4.9. These are often professional-grade units designed to handle tough work. They’re often used, for instance, to clean construction sites or to maintain truck fleets.
Pressure washers tend to have four main nozzles, each with different uses. Understanding the correct use can prevent damage while ensuring cleaning safety and efficiency.
The red nozzle produces a very powerful, concentrated water jet. It’s the strongest of all nozzles, so it’s best for removing very tough stains and dirt from durable surfaces like concrete and metal. It can also be used to remove rust from steel, but it can damage softer materials, so it shouldn’t be used on wood or siding.
The yellow nozzle produces a slightly wider spray than the red nozzle, but it’s still quite strong. It strikes a nice balance between power and coverage. This nozzle is perfect for stripping paint, removing mildew from hard surfaces, and preparing surfaces for fresh paint.
The green nozzle produces a wider spray than the yellow nozzle, which means less intense pressure. This nozzle is quite versatile, and it’s ideal for basic cleaning tasks like washing decks, siding, and patios. It’s also a good option for removing mud from vehicles and equipment without causing damage.
The white nozzle produces the widest angle spray, so it’s the gentlest of all four nozzles, but it also covers the largest area. It’s best for delicate surfaces and other materials that might incur damage from higher-pressure nozzles. It’s commonly used for cleaning windows, washing down outdoor furniture, and rinsing off vehicles.
If you’ve shopped around and you’re still not sure what kind of pressure washer will best meet your needs, you might call in a professional pressure washing company. They can assess your job and provide a cost estimate for professional power or pressure washing. Then you can decide once and for all if you prefer to DIY your pressure washing project or have them take it off of your hands.
A good psi for a pressure washer depends on what you plan to wash, but as a general rule of thumb, you should look for one that reaches 2,000 to 3,000 psi when you’re out shopping. 3,000 psi is plenty powerful for most homeowners’ needs, and the lowest settings on these machines should be suitable for surfaces like wood and siding.
Most pressure washers come with a life expectancy of up to 500 hours of use. That may not sound like a lot, but given that many homeowners only use the machine for up to 50 hours per year, that means your pressure washer should last you for a solid 10 years.
You can use a pressure washer to clean a whole host of surfaces. The exterior siding of your house is one of the most popular spots, as well as your driveway, garage floor, patio or deck, and even your outdoor furniture. Just be mindful about the amount of pressure you apply to different materials—concrete can handle a lot more than wood, for example.
