Stains at vents/roof

Stains around roof top vents.

The roof was one layer standard 3 tab shingle about 10 years old. Gable/moderate slope.
House had soffit/gable/roof top venting. Insulation was loose fill about 6-9 inches. No moisture stains in attic, ventilation seemed to be adequate.

So what is causing the stains around the vents?
How would you report the scenario?

Would an active vent like a power vent be an solution? Or maybe adding more soffit vents. (There were no baffles installed but the insulation was not blocking the vents.

Thanks for the time.

150209 020 (Small).jpg

150209 020 (Small).jpg

Did the rooftops of neighboring homes have the same problem?

I did not look at any other roofs.

I don’t know. It looks like some kind of airborne particulates coming out of the attic plated out on the shingles. The source of the particulates?

  • What’s the fuel for the heating system?
  • Did any exhaust flues terminate in the attic, including bathroom vents?
  • Was there a whole-house fan?
  • Was there any discoloration of wall or ceiling surfaces in the living space or of framing or sheathing in the attic?
  • If moist air was evacuated through the roof vents, it could be algae, although if those roof vents were galvanized and that was algae, there would be clear streaks on the downhill side from runoff, since algae doesn’t like zinc.

Do they have a wood fireplace?

Looks like over spray pattern to me (like spray paint or some chemical put on the vents). Certainly is interesting what ever it is.

Good question Kenton. Looks like an unexplained anomoly to me. If there was no dicernable damage I might not call it out, or you might recommend to monitor it.

Either way great pic and interesting :smiley:

No stains at plumbing stack.

Yes the home did have a wood burning fireplace. It was at a lower level slab.

Got any attic pics?

This was a Condo building roof ,so I never got to the attic or roof due to no access.

22 footer not enough, but I did notice the stains.

No, there were no visible issues. In the upper attic. Insulation, roof structure and even the ventilation seemed fine.

The lower attic had some indications of past leaking from an upper rrof downspout discharging onto the lower roof surface. (They recently extended)

Your picture looks like a one time event the way it is all so even .

They were not shadows as it was cloudy. Maybe I was in the twilight zone!!

Is there a possible leak in the attic from the fire place?

sure looks like smoke damage David but You are not saying anything that would indicate that as a possibility…maybe it was martians…:shock:

“The home appeared to be haunted. The Inspector recommends that you go see Paranormal activity”.

It seems that way. Maybe it should be on Ghost Stories.

The owner/seller of that home has been haunting me lately.



ALSO note the box out they installed UNDER the vents?? i think to catch drips from wind driven rain? Could this be a contributor? more heat?

Inside my house, there were dust/ shadow stains around where paintings used to be for so long.

the home had the OHARE new windows installed and the doors weather sealed etc…

i’m considering it’s something having to do with pressure inside the home? old attic dust plating out, same as like a shadow around wall hangings???

same ROOF, AS I MENTIONED ABOVE there are box outs installed underneath vents…

btw- No signs of a fire inside attic of home…

Fireplace in the basement back-drafted and sent all the smoke up through the attic. Since it was cold the particulate settle out around the vents. Owner probably opened the basement windows to get the smoke out and up the smoke goes finding any exits into the attic. The reason may be that they did not get a hot enough fire to start heating up the chimney.