Pressure Washer

Pressure washers used in professional roof cleaning are significantly more powerful than domestic models. Commercial-grade units deliver water at pressures of 3,000 to 4,000 PSI (pounds per square inch) with flow rates of 15 to 20 litres per minute, powered by petrol engines or three-phase electric motors. The combination of high pressure and high flow rate is what enables effective removal of deeply embedded moss, lichen, and grime from porous tile surfaces. The pressure washer nozzle type and angle are critical for effective and safe roof cleaning. A zero-degree (pencil jet) nozzle provides the highest pressure but covers the smallest area — it is used for removing stubborn biological growth. A 15-degree or 25-degree nozzle spreads the spray over a wider area and is used for general cleaning. A turbo nozzle (which spins a zero-degree jet in a circular pattern) provides a good balance of cleaning power and coverage. The nozzle is held at an appropriate distance and angle to clean the surface without driving water under tiles or damaging the substrate. In Gippsland, Town & Country Roofing uses commercial-grade petrol-powered pressure washers with variable pressure settings and interchangeable nozzles. Each roof is assessed for the appropriate pressure and technique — lower pressures for fragile or deteriorated tiles, higher pressures for heavily soiled metal roofs. The cleaning process typically takes 4 to 8 hours for an average residential roof and is always completed before any coatings or repairs are undertaken.