HarborGemHigh pressure and roofs do not mix. It can lift tiles, strip the granules from shingles and force water underneath. That is why roof cleaning is done with a soft wash: a cleaning solution that kills the growth, followed by a gentle rinse.
What you are probably seeing
- Black or dark streaks running down the slope, usually algae
- Green patches or moss in shaded areas and along edges
- Lichen that looks like small crusty spots
- Dirt and debris collecting in valleys and behind chimneys
Why it is worth doing
Growth holds moisture against the roof surface and can shorten its life. Dark streaks also make the whole house look older. Cleaning a roof is usually less expensive than replacing it early.
Tile and shingle roofs
Tile and asphalt shingle roofs are cleaned differently, and some roofs are not safe to walk on. We will assess the roof type, pitch and access when we quote, and tell you if a roof is better left alone.
Common questions
Something else on your mind? Call 714-900-1957 and ask.
What are the black streaks on my roof?
On asphalt shingle roofs they are usually a type of algae that spreads down the slope. It is common in humid coastal areas.
Is a soft wash safe for my roof?
Soft washing is the standard method for roofs because it avoids the damage that high pressure can cause. We will check your roof type before we quote.
Will the streaks come back?
Growth can return over time, especially in shade and damp air. Cleaning slows the cycle, and we can suggest how often to repeat it.
Can you clean the gutters or house at the same time?
House washing pairs well with roof cleaning. Mention what you want in your quote request.
Where we do this work
Based in Newport Beach and Huntington Beach, serving homes and businesses across Orange County.