roof discoloration

Hi
I am about to replace the roof on my house. I noticed that the shingles around the heating exaust vent are covered with some white stuff. I asked the roofer what the cause might be and he had no clue. Does anyone observed something similiar? I don't want my new roof to be spoiled in a few years. Maybe the exaust vent has to be taller?
Yuri.
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In alt.home.repair

Is it like that only around that vent or all of them? Many roofs get fungus growth in a line below all the roof jacks because the rain water doesn't wash as well there. For you new shingles, be sure to get anti-fungal coated shingles to eliminate this problem.
As for your furnace vent, it may be something else. Is it uniformly distributed around it or just on the downslope side? I'll bet it is a fungus, though usually those are black.
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wrote:

anyone
few
It is only around one vent. I have an another heat vent that is attached to the water heater. There is nothing around this one.
The not heat vents (from plumming) are all OK.

It is all on the downslope side.
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ruminated:

Are you sure that the flashing wasn't painted with white roofing paint (to seal it) that leached onto the shingles over the years?
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Eric Lee Green mailto: snipped-for-privacy@badtux.org



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Nope.

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