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.
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.
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.
To correctly strip old paint, you should work with a power washer with a psi of 2000 or higher. Even starting out at 2000 probably won't do the trick and you'll need to set the psi closer to 3,000 for effective paint stripping.
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.
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.
If you want to clean your driveway quickly and efficiently, use a pressure washer of at least 3100 PSI. Using pressure washers with pressures ranging from 1000 to 2300 PSI will also help you clean your driveway, but it will take a long time.
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.
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.
For a typical car, use 1,200 to 1,900 PSI and 1.4 to 1.6 GPM for 1,900 to 2,800 cleaning units. Anything above risks the car's coating and paint. Electric vs. Gas: In general, gas-powered pressure washers tend to deliver more power.
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). Determine whether you will rent or buy your machine.
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.
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.
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.
Applying a degreaser will loosen stains in the concrete, allowing you to pressure wash them away. Some pressure washers have an attachment tool for applying degreaser. Otherwise, scrub the degreaser into the concrete with a stiff-bristled brush or push broom.
While you know that using a power washer can almost magically erase built-up dirt, debris and stains from practically any surface, you might wonder: Can power washing damage concrete? The quick answer is yes, power washing can degrade a concrete surface.
Tip: Only use low pressure when washing the exterior brick on your house. Pressure washing using 500 to 1000 PSI is recommended for cleaning masonry. Many professionals use 100 to 1500 PSI to avoid damage. 2,000 PSI is the absolute maximum, and that's for experienced pressure washers only.
If the pressure is set too high, it may ultimately damage your vinyl fence. It's best to start at a lower setting and adjust accordingly to your personal need. Usually, 500-800 PSI is an acceptable range to start with.
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.
The higher the PSI the more durable your concrete will be and will thus be resilient to cracking. The average residential project uses a minimum of 2,500 to 3,000 PSI; however if you're concerned about cracking then we recommend talking to your concrete contractor about stronger products on the market.
RECOMMENDED CONCRETE THICKNESSES
Medium Use: 5" to 6" concrete - Driveways and parking areas for light to medium trucks plus occasional use by heavier trucks. Heavy Use: 7" or thicker concrete - Driveways and parking areas for heavier commercial and industrial trucks.
In residential concrete, 4 inches is the minimum thickness for walkways and patios. Garage slabs and driveways should be 5 to 6 inches thick if any heavy truck traffic is anticipated, otherwise 4 inches is adequate.
A medium-duty pressure washer is strong enough to blast greasy, grimy stains from residential areas. Homeowners can safely clean sidewalks, concrete driveways, decking, and siding with a 2,000 to 3,000 PSI washer.
Most people believe that concrete is solid and almost invincible. However, using a pressure washer with the incorrect tip or using too much pressure or a combination of the two can etch concrete.