High-PSI 3,500+ for concrete and brick: driveways, walkways, brick paver patios, exposed aggregate. These surfaces handle hard pressure fine and benefit from a surface cleaner attachment for even results. Mid-PSI 1,500–2,500 for wood and composite: wood decks, composite, painted concrete. Enough pressure to clean. Not enough to damage the surface or strip paint. Soft-wash for vinyl, aged brick, and painted wood: low pressure under 500 PSI with a chemical applicator. The cleaning solution does the work. Critical for vinyl siding because high-PSI cracks the seams and damages the vapor barrier. Aged brick from 1900s–1950s crumbles under high pressure. Painted wood gets stripped. Common Toronto mistakes: renting a pressure washer for vinyl siding leads to cracked siding and water behind the seams. High-PSI on a wood deck gouges grain, creates splinters, requires sanding to fix. Power-washing the foundation injects water into mortar joints, causing freeze-thaw damage that winter. What we do: assess every surface, match the pressure, pre-treat with biodegradable solution, then wash. Walk-through with photos before invoice. Right method, every time.