Simply choosing the right pressure washing equipment is only the start. After receiving proper training in how to use it, all the elements must be put together properly for optimum effect.
This article provides information on how to get the most out of your pressure washing equipment.
Two types of pressure washers and how they work
Pressure washing is a lot of fun to do—and rewarding in terms of results—that you’ll be searching for concrete driveways, sidewalks and stairs to clean once you’ve finished your own. You can rent or buy a pressure washer to clean many outdoor surfaces. Discover how to clean concrete safely and efficiently by following the pressure washing tips below.
Pressure washing equipment is either powered by an electric motor or gas engine, runs a pump that pressurizes the water from your garden hose to 1,000 lbs. or more then forces water out through a spray wand. The higher the pressure (measured in pounds per square inch—psi), the tougher the cleaning jobs they can tackle. Both types require a steady, uninterrupted supply of water (in gallons per minute—gpm). Most homeowners will find that pressure washing equipment with a pressure range of 1,300 to 2,400 psi works best for occasional home use.
Electric pressure washers deliver 1,300 to 1,400 psi, require about 1-1/2 gpm and are the best choice for light-duty cleaning like washing cars (Photo 3), outdoor grills and garage floors (Photo 4). They generally cost less and are quieter, lighter in weight and more portable than gas-powered washers. Remember that water flow rates of less than 4 gallons per minute – found on general consumer (homeowner) units – are not high enough to be competitive because of increased cleaning time, which raises labor costs.
Most pressure washing equipment that you’ll find for rent or sale are gas-powered. This type can deliver higher water pressure than the electric kind, some more than 3,000 psi. But gas-powered washers also require more water: 2 to 3 gpm. These washers are the best choice for bigger jobs. You can usually rent one at a tool rental store or home improvement store.
Commercial contractors generally use 4 to 6/gpm at 1500 to 3,500/psi for most cleaning applications. An exception to this is wood cleaning. Here 500 to 2,000/psi is preferred to reduce any damage of the wood.
Washing Tips and Techniques
- Always wet the surface with water before pressure washing. Presoaking helps to soften unwanted moss and mildew buildup
- Hot water is a better solvent than cold water
There are two factors that need to be considered when choosing the proper nozzle: the nozzle orifice size and the spray angle. These determine the gallons per minute at a particular pressure of the water flow. To choose your nozzle size you need to know the gallons per minute (GPM) and pounds per square inch (PSI) necessary for the job you are doing.
When the nozzle size increases, the PSI of your pressure washer is reduced while the flow remains the same. By reducing the pressure of your washer with the nozzle, you will decrease both the PSI and GPM. Knowledgeable contractors reduce the PSI of their pressure washers by increasing nozzle size in order to keep the GPM at its maximum.
Spray Nozzles for Different Tasks
Pressure washers that deliver less than 2,400 psi generally come with a single adjustable spray nozzle that delivers zero to 60-degree fan patterns. Some brands offer accessory “rotating” or “turbo” nozzles that clean more effectively than standard adjustable nozzles because they spin the water stream.
Heavier-duty units generally come with four or five color-coded, individual nozzle tips (three are shown here). They create specific fan patterns: wider (for using detergents), medium (for general cleaning) and narrower (for blasting deep stains).
Important note: Point the spray wand away from people and property when starting the pressure washer.
Understanding PSI (Pounds per Square Inch)
Water pressure from the pressure washing unit is measured in pounds per square inch or PSI. This pressure is the amount of force delivered to the surface being cleaned, and is the critical factor in breaking debris from that surface. PSI is determined by the orifice size of the nozzle tip and the flow rate (GPM). Remember, as nozzle size increases or decreases so will PSI fluctuate accordingly.
Cleaning concrete sidewalks, driveways and stairs
Because of its light colour, concrete can become very unsightly very quickly given the right conditions. Concrete is a porous material and it harbours moisture and dirt promoting the growth of mould. Concrete cleaning for Higher Ground Gardens is straight-forward because we have the right pressure washing equipment. High-powered commercial pressure washing accompanied by the right nozzles are the only sure means of removal.
Request an estimate for your pressure washing service by filling out the form online today. See sidebar. Or call 778-323-1502 to schedule a free estimate now.