Those dark streaks will not wash off in the rain.
Dark streaks, algae and moss grow on roofs, especially on shaded slopes in humid weather. They make the whole house look older, and moss holds moisture against the roof.
A roof should never be blasted with a pressure washer. We clean roofs with low pressure so nothing is stripped or lifted. Send a photo, tell us the roof type, and we will tell you how we would clean it.
Three kinds of roofs.
Each one gets cleaned the way that suits the material.
Shingle roofs
The most common roof on a house. Black streaks and green moss show up first on the shaded slopes. We clean with low pressure so the surface stays intact.
Metal roofs
Metal sheds water, but it still collects dirt, pollen, algae and streaks. We clean it gently so the finish is not scratched.
Spanish tile roofs
Tile has texture and edges where moss and algae hold on, and it is fragile. The work is done carefully and with low pressure.
Common questions
A roof should be cleaned with low pressure, never blasted. That is how we approach shingle, metal and tile. If your roof is old or already damaged, we will tell you what we see before we start.
Usually, yes. The dark streaks on shingle roofs are commonly algae. Moss is a separate growth that sits on top of the roof. We can usually tell you what you have from a photo.
It depends on shade, trees and humidity. Shaded slopes grow algae back faster than sunny ones.
Move cars and patio items away from the edge of the house and close your windows. We will tell you if there is anything else.
More from Prime Line
Want your roof looking new again?
Text or call, and send a few photos if you can. Serving Conroe, The Woodlands, Magnolia and the rest of Montgomery County and surrounding areas.