Power Wash the Deck

Start with the pressure at 500 to 600 psi and test it on an inconspicuous area. Increase the pressure incrementally as needed to clean the deck without damaging or etching the wood surface.

Engage the trigger while holding the wand tip a couple of feet away from the deck surface, then lower the wand to about 12 inches above the surface. Clean the deck with a sweeping motion, and avoid the tendency to pivot with your arm, which will result in ​an inconsistent distance between the spray tip and the deck surface. Try to maintain a consistent distance by moving your arm laterally back and forth.

Clean the deck boards from the house outward. Work with the grain by feathering the spray lengthwise, parallel to the deck boards, and overlapping each area slightly. The goal is to achieve even cleaning with no "hot spots" or visible "cleaning edges."