The ideal frequency for pressure washing depends on the surface being cleaned and your local environmental conditions. For a home's exterior with siding that is safe to wash (such as vinyl, cement, or aluminum), a full wash once or twice a year is a good guideline to remove accumulated dirt, grime, mold, and mildew. You may need to wash more frequently if you live in an area with heavy rain or snow, near a dirt road, or if you notice excessive buildup. Other surfaces have different schedules; for example, a frequently used driveway may need cleaning more often, while outdoor patio furniture might only need to be washed every few years. Use your discretion based on how dirty the area gets.

Powerwashing services for businesses typically range from $200 to $1,500, depending on surface size, level of grime, and cleaning methods. Heavily stained or high-rise buildings may require additional labor and equipment.

Filling small cracks in your driveway with patching material is usually the most affordable fix, costing about $2 to $3 per square foot. For larger damage, however, these repairs won’t last, so it’ll save you more to resurface or replace the driveway, depending on the extent of the issues.

You should avoid using a pressure washer on any surface or item that could be damaged by the high-pressure spray, as some materials are too delicate to withstand the force.

Key items and surfaces to avoid include:

• Electrical Components: Never pressure wash electrical systems, as water can cause short-circuits and create a safety hazard. This includes utility meters, breaker boxes, electrical outlets, generators, and HVAC or air conditioner units.

• Delicate and Fragile Materials: Fragile items can crack, shatter, or be stripped by the pressure. Avoid pressure washing windows, glass, light fixtures, shingled roofs (especially asphalt), and stucco.

• Painted, Stained, or Sealed Surfaces: Unless your goal is to strip the finish, do not pressure wash painted surfaces, stained wood (like decks), or anything with a protective seal that could be stripped away. Be especially cautious with older surfaces that may contain lead paint.

• Soft Woods and Certain Decking: Delicate surfaces like softwood, composite decking, and antique or wooden patio furniture can be etched or damaged. If you must wash wood, use a lower-powered pressure washer with a wide-angle nozzle to prevent damage.

• Living Things: Never use a pressure washer on people, pets, or plants. The force can cause serious injury and will destroy landscaping.