How to pressure wash concrete patios, driveways and walkways

If you have a concrete surface to clean, pressure washer would be the tool of choice. Off-course you can try to clean concrete with garden hose and brush, but if you have ever tried this undergoing you would know to leave garden hose and brush in the garage.

You can rent or purchase a power washer and clean the concrete yourself, or higher a contractor who offers pressure washing services and has commercial grade equipment.

If you're going to power wash your concrete yourself, make sure you know what you're getting into before you begin. 

Here are some important tips:

• Plan for at least 2-4 hours for this project
• Dress in long pants and sturdy shoes
• Some people also wear gloves and safety glasses
• Apply a degreaser or concrete cleaner before power washing
• Start at the highest point and work your way down
• Keep the nozzle about 12" from the surface, getting too close could cause damage
• Use a steady, sweeping motion as you move back and forth across the concrete
• Consider sealing the concrete after it has completely dried

Keep in mind that every concrete surface is different. Older concrete or concrete that has been stamped or stained may respond differently to the powerful stream of water. Test and check your results in a less visible spot before proceeding to clean the entire surface.

There are many different pressure washer options to consider, including:

• Small, light-duty units you attach to a garden hose
• Big, commercial-grade machines
• Various levels of pressure (PSI)
• Gas and electric models
• Wheel-mounted, walk-behind surface cleaners

Flow rate and nozzle type

Once an adequate water pressure is established, flow rate determines the cleaning speed, especially how fast contaminants are flushed from the surface. Heavily soiled concrete, requires higher flow rates. Several contractors recommend a power washer with a volume output of 5 or 6 gpm. When cleaning vertical surfaces, higher flow rates are not as critical because gravity helps contaminants flow from the surface.

Cleaning speed also can be increased by using a rotary nozzle instead of a standard fan nozzle. To produce a fan pattern, standard nozzles deflect the water on an angle, which slows the water down. Rotary nozzles spin an undeflected water jet in a circular path, so the water leaves the nozzle with greater speed.

If you think pressure washing your concrete surfaces is to much hassle for you, consider hiring pressure washing contractors near you who have the right equipment and kn ow how.