Soft wash vs power wash

Power washing relies on high-pressure water to mechanically remove dirt, mildew, paint, and surface contamination. Effective on concrete, brick, stone, and other hard, durable surfaces. Risks: forcing water behind siding, damaging painted surfaces, etching softer materials, voiding shingle manufacturer warranties.

Soft washing uses low-pressure water (under 500 PSI, often sub-100 PSI) combined with chemical cleaning solutions (typically a sodium hypochlorite + surfactant blend) that kill mildew, algae, and biological growth while breaking down dirt. The chemicals do the cleaning work; the water rinses. Effective on roofs, vinyl siding, stucco, painted surfaces, and any surface where high pressure would cause damage.

For pressure washing operators, both techniques are required for a full service offering. Equipment is largely the same (4 GPM gas-powered washers); soft washing adds chemical injection systems. Pricing is similar per square foot but margins differ based on chemical cost and crew time. Some operators specialize in soft wash exclusively (roofs, residential siding) where the technical difficulty and customer trust required justify premium pricing.