Light-duty pressure washers are rated at 2,000 PSI or less and are suitable for cleaning automobiles, motorcycles, boats, bicycles and all-purpose cleaning. Medium-duty pressure washers produce 2,000 to 3,000 PSI and can be used to remove grease and grim from concrete, sidewalks, decks and siding.
Mid-Range Power: 2,000 to 3,200 PSI
The most versatile category of pressure washers, those ranging from 2,000 to 3,200 PSI effectively clean cars (including the most well-used off-road vehicles), home siding, fences, boats and grimy garage floors. Those closer to 3,200 PSI work effectively on tough stains, too.
Although many electric pressure washers produce a pressure of about 1900 psi, you should only use a water pressure of 1500 psi or lower on your car. You'll need to look for a low-pressure machine that's a bit less aggressive than the standard.
Best for home and shop use, these sturdier, more powerful units make it easy to clean everything from exterior siding and fences to patios and decks. Heavy Duty and Commercial: Heavy-duty pressure washers start at 2800 PSI at 2 GPM or more.
2,000 - 2,900 PSI: This is a moderate strength unit used heavier residential tasks. These units are commonly sold as either electric or gas pressure washers. 3,000 - 6,900 PSI: These high pressure models are what professional pressure washers and contractors usually use.
Concrete cleaning calls for powerful pressure washers featuring high pressure levels of 3000 PSI. However, if you will be using the power cleaner to maintain a range of surfaces in addition to concrete, choose one with adjustable pressure levels and set it to about 3000 PSI when you need to clean concrete.
Medium Duty 2000-2800 PSI
This classification ranges from as low as 2,000 PSI to as high as 2,800 PSI. You can use a medium-duty pressure washer for almost any surface. They're great for cleaning concrete, brick, and wood.
Choosing a Pressure Washer
Vinyl siding can withstand a powerful gas pressure washer (2,500-3,000 psi). Aluminum, stucco or soft-grain wood homes will do better with a less powerful washer (about 1,200-1,500 psi).
For cleaning a wooden deck, you'll be best served by using the lowest pressure setting that's still effective. For soft woods like cedar or pine, this is usually about 500 to 600 psi. For harder woods, it can go up to 1200 to 1500 psi. Choose the right tip to use as well.
To clean a deck, some homeowners choose a washer with a pressure range of 1,300 to 2,400 psi, the same as washing a car. HGTV recommends working with the lowest pressure that cleans your deck materials gently: about 500 to 600 psi for soft woods like cedar or pine, and up to 1200 to 1500 psi for pressure-treated wood.
PSI Pressure range for Different Surfaces
Different surfaces require different levels of PSI pressure. Generally, for most residential uses, an electric pressure washer (less than 2000 PSI) will suffice. Soft surfaces, such as decks and siding, usually require more cleaning power than harder surfaces such as driveways.
Every home is unique, from its square footage to the materials it's made from, making it difficult to give an exact estimate. For example, a 2,000 square foot home can take anywhere from one to three hours to power wash.
You'll need a power washer that provides a force of 3,000 PSI or more. The higher the pressure, the better and faster is the cleaning. If you want to use a lower pressure on certain surfaces, you can always attach a larger spray tip to it.
Concrete and asphalt require more cleaning power. You'll want to use the turbo nozzle on the 1600 PSI for hard-to-clean driveways, sidewalks, and patios as well as brick paving. For wood decks and painted surfaces, switch to the gentler 40-degree nozzle.
The main difference is that power washing uses highly pressurized steam to do the cleaning while pressure washing just uses unheated tap water, without the help of a heating element.
If you need to clean a two-story house, you'll need a heavy-duty or extra heavy-duty pressure washer. This will give you a water pressure of 2,800 PSI (Pounds Per Square Inch) or higher and three to four GPM (gallons per minute) of water.
There's no doubt that electric pressure washers from 1,300 to 2,300 psi can wash a concrete driveway, but it'll take longer. If you have a large driveway with lots of stains, you'll want more power to do the job faster. I chose the 3,100-psi gas pressure washer and cut the job time in half.
2,000 to 3,000 PSI
Good for cleaning concrete surfaces with light to moderate oil stains, most automotive cleaning, pools, many industrial applications.
From there, you can work your way up, though it is generally best not to exceed 2000 PSI. It is also essential to use the right nozzle tip for the job. Don't use a narrow nozzle that will focus water too much in one area, as this may crack the grout or bricks. A nozzle that fans the water out is best.
The bare minimum is usually between 2,000 and 3,000 psi for fill and simple surfaces (e.g., patios or sidewalks). ACI sets 2,500 psi as the structural concrete minimum. Pavement, slabs, and footings can be up to 4,000 psi. Suspended slabs, beams, and girders (typically found in bridges) might be 5,000 psi.
Powerful pressure washers with too much PSI will damage concrete when power washing. Most residential driveways require no more than 3000 to 3500 PSI for proper and thorough concrete washing. Heavy-duty commercial pressure washers and other power washing equipment are too strong for the average residential driveway!
Your pressure washer should have a minimum pressure rating of 3000 psi to effectively clean your sidewalk. There are a few situations where a higher pressure rating might be needed, but exterior cleaning experts all agree and recommend that 3000 psi is appropriate for residential use.
A strength of 4,000 psi (pounds per square inch) after a one month cure is the industry minimum for concrete driveways, slabs, and sidewalks. However, 4,500 psi as the ideal. According to guidelines published by AsktheBuilder.com, a home foundation requires a thicker pour of 8-10 inches and a psi of 3,500-4,000.