The answer to 'pressure washing dirty' is that pressure washing can be an effective way to clean a variety of outdoor surfaces, but it requires careful technique to avoid damage. Common causes of dirty surfaces that need pressure washing include accumulated dirt, grime, mold, mildew, and other environmental buildup. Symptoms may include discolored, stained, or unsightly surfaces.
For DIY pressure washing, it's important to use the right pressure settings, nozzle, and cleaning solution to match the surface material and avoid damaging it. Surfaces like wood, stucco, and siding may require lower pressure to prevent gouging or peeling. Calling a professional pressure washing service is recommended for larger jobs, delicate surfaces, or when dealing with mold and mildew that could require specialized cleaning agents.