But there are other roof stain colors and causes.
Stains on roof stacks.
Roof stains are not only unappealing to look at they also compromise the waterproofing ability of your shingles.
Preserve the appearance of your roof by removing black stains promptly.
The most common type is known as gloeocapsa magma also known as blue green algae.
The leaking may first be seen in the attic but if you don t catch it right away you may see water coming into the house dripping on the floor.
These are commonly seen underneath roof vents plumbing stacks vent hoods.
Roof vents are made from different materials.
Algae can be killed and the stains removed using chemical cleaners though they usually return over time.
When that happens it is generally caused by mildew algae mold or dirt stains.
A roof that leaks around a vent pipe is a common cause of small water stains on a ceiling or water leaking into a home.
Roof shingles are exposed to a lot of wear and tear as extreme heat sun wind and precipitation come into contact with them.
This algae growth usually begins as small spots and then eventually becomes visible streaks.
While doing little harm to your shingles the black streaks caused by the algae are unsightly.
Dark black or brown roof shingle stains are often caused by black algae bleed through or extractive bleeding of asphalt dirt soot or organic debris.
As far as snow just got it a few days ago and little to none last winter 10 inches total maybe.
Expect to see rust stains only around and below rusting metal components on a roof.
These substances can infiltrate the limestone mixture that attaches the shingle to the roof and end up harming its ability to repel water.
12 31 2012 04 08 pm 14.
Although these dark spots and ugly black streaks on your roof may look like dirt mildew soot or mold what they really are is algae.
The remedies for and means of preventing stains on roof shingles are discussed as well.
Your stains are probably caused by the airborne spores of a blue green algae known as gloeocapsa magma which is often mistaken for mold or mildew.
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Roof stains caused by fuel oil dye.
Valid point on upslope side of stack little or no stains showing there.
Rust staining red or brown rust stains on asphalt roof shingles or on metal roof surfaces metal roof flashings metal chimneys antenna mounts or other metals that rust can stain roof surfaces a red or reddish brown color.