Answer-first:
Yes—when done using a soft wash method, roof cleaning is completely safe for asphalt shingles and is even recommended by most manufacturers.
Why Soft Washing Is the Only Safe Method
– Uses low pressure (under 100 PSI)
– Applies an algaecide to kill black streaks and moss
– Doesn’t disturb granules on the shingle surface
High-pressure cleaning should never be used on asphalt shingles.
What Happens If I Don’t Clean My Roof?
– Algae retains moisture and breaks down shingles
– Moss roots can lift edges and allow water intrusion
– Your roof’s lifespan can be shortened significantly
Can Roof Cleaning Void My Warranty?
Using high pressure can—soft washing maintains your warranty, and many manufacturers now recommend it.
How Long Does It Take?
Most residential roofs take 2–3 hours, depending on size, pitch, and buildup. Full results appear over several days as the algae breaks down.
Will Cleaning Remove Moss?
Yes. The soft wash kills moss and algae at the root. Moss will brown and naturally fall away over time. Avoid scraping—it can damage shingles.
When Should I Schedule Roof Cleaning?
– Spring or fall are ideal in Columbia, SC
– After a pollen-heavy season
– When black streaks or moss appear
Get more answers at elevationpowerwashing.com
Pressure Washing FAQs 
Leave a comment