Traditional high-pressure power washing can cause significant damage to most roofing materials and should be avoided. The intense pressure strips protective granules from asphalt shingles, potentially removing years of useful life in a single cleaning. On tile roofs, high pressure can crack or dislodge individual tiles while forcing water under the tiles where it damages underlayment. Even metal roofing can sustain finish damage from excessive pressure. Professional roof cleaning services use low-pressure washing systems (sometimes called “soft washing”) combined with appropriate cleaning solutions that remove biological growth and debris without physical damage. This gentler approach effectively cleans without compromising your roof’s integrity or manufacturer warranties. When interviewing roof cleaning companies, specifically ask about their pressure settings and cleaning methods to protect your investment.
