Soft Wash vs Power Wash: Which Is Right for Your Roof?

Never High-Pressure Wash Most Florida Roofs

This is the single most important thing Florida homeowners need to know about roof cleaning: high-pressure power washing can permanently damage your roof. For most roof types — asphalt shingles, tile, and metal — soft washing is the correct and recommended method.

What Is Soft Washing?

Soft washing uses very low water pressure (typically 50–100 PSI vs 1,500–3,100 PSI for standard pressure washing) combined with a biodegradable cleaning solution containing sodium hypochlorite. The chemicals do the cleaning work, while the low-pressure water rinses away debris.

Soft washing is effective at killing:

Gloeocapsa magma algae (causes black streaks on shingles)
Moss and lichen
Mildew and mold spores
Bacteria and biological growth

Why Power Washing Damages Roofs

Granule loss on asphalt shingles — The protective mineral granules are blasted away, accelerating aging and voiding manufacturer warranties
Cracked or displaced tile — Florida tile roofs are especially vulnerable to high-pressure damage
Lifted flashing — High pressure can force water under flashing, leading to leaks
Warranty voidance — Most shingle manufacturers specify that power washing voids the warranty

How to Know What Your Florida Roof Needs

Asphalt Shingle Roofs

Soft wash only. The Asphalt Roofing Manufacturers Association (ARMA) recommends a low-pressure sodium hypochlorite solution for cleaning shingles.

Tile Roofs (Barrel Tile, Flat Tile)

Soft wash strongly preferred. Tile can be pressure washed at very low PSI by experienced professionals, but improper technique breaks tiles.

Metal Roofs

Low-to-medium pressure washing is generally safe for metal roofing. Soft washing is still effective and gentler. Avoid high pressure on any painted or coated metal surfaces.

Questions to Ask Your Roof Cleaning Contractor

"Do you use soft washing for roof cleaning?" (Answer should be yes for most FL homes)
"What chemicals do you use, and are they biodegradable?"
"Will your cleaning method void my roof warranty?"
"Do you have experience with [my roof type] specifically?"