Soft washing uses low water pressure combined with a cleaning solution to break down algae, moss, and dirt on a roof's surface, avoiding the shingle granule damage that high-pressure washing can cause. This is the standard method for residential asphalt shingle roofs in Central Iowa.

  • Low-pressure application safe for asphalt shingles
  • Breaks down algae, moss, and surface grime
  • Avoids granule damage from high-pressure washing

Current Roof Cleaning Trends

  • Soft washing has become the industry-recommended standard over pressure washing

    Roof manufacturers and the Asphalt Roofing Manufacturers Association do not approve pressure washing for asphalt shingles — high pressure dislodges protective granules and disturbs shingle edges, while soft washing kills algae and moss at the cellular level without damaging the roof surface. (ARMA / industry roof cleaning guides, 2026)

  • Untreated algae can meaningfully shorten roof lifespan

    Gloeocapsa magma, the algae behind common dark roof streaks, feeds on the limestone filler in asphalt shingles and can shorten roof life by 5-10 years if left untreated — regular soft washing addresses this directly. (Industry roof algae/shingle lifespan coverage, 2026)

This content is reviewed by the Des Moines Roof Cleaning editorial team and informed by licensed-contractor sourcing, manufacturer documentation, and established industry standards for Roof Cleaning. Read our editorial standards.