3 Major Myths About Pressure Washing (a 3 part series)

The More Pressure the Better

Most believe that water pressure (psi) is what does the cleaning; after all, it is called a pressure washer. The truth is that excessive pressure will force water where it’s not wanted and can damage surfaces such as vinyl siding, wood, asphalt shingles, and certain types of brick and concrete. No more than 1,000 psi should be used to clean wood, or wood fibers can be damaged, causing unsightly scars and wand marks that will show through the sealer. More than 800 psi can force water behind vinyl siding causing water damage. No more than garden hose pressure should be used on asphalt shingles, or shingle granules will be washed away, lessening the longevity of your roof. The proper way to clean these surfaces is to rely on the cleaners to do the work and then use low pressure to rinse clean. The lowering of the psi is achieved by changing the tip or nozzle, at the end of your wand, to one with a larger orifice. Make sure the contractor you hire uses the low pressure cleaning method.