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kok328 03-09-2008 08:40 AM

Stack Frost
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I noticed this morning that I had ice built up around the base of my water heater/furnace exhaust.
Never having witnessed such an occurence, I was wondering if this is normal or do I have another task to add to my list.
I suspect that there is an air gap leak that is freezing moist air escaping through the roof.
See attached Pic.

inspectorD 03-09-2008 06:29 PM

Ever hear of ice damming...same issue. Get some insulation around the pipe inside. The temps are low coming from the vent.
Should stop the problem.

kok328 03-10-2008 03:44 PM

Yep, I'm all too familiar w/ice damming (MI resident here) and this is not ice damming. Notice the absence of any snow or ice on the surrounding roof structure and/or the remaining circumference of the pipe. Also, this is at the peak of the roof not over the soffit areas.

My attic is blow pink fiberglass and I hate that stuff w/a passion. By the time I get out of the attic, I'll be wearing it. However, if this can't be tackled from the outside, I'll have no choice.

inspectorD 03-10-2008 04:20 PM

Let me clarify.
Yea, I was tryin to keep it simple....I know it's not ice damming, but it is condensation from on a warm pipe compared to a cold outside temp. The reverse happens to your cold beer or soda on a hot day in July...only it doesn't freeze.
The pipe is creating condensation through a thermal bridging. Metal is the culprit, you cannot fix it unless you have a thermal break, basically the insulation will help with that to slow the temperate difference. It will not solve it for extreme temps, but nothing will.
Good luck.

You could also have a leak in the upper part of the pipe connection.

tomtoolman12345 03-11-2008 09:03 AM

Put in a double wall pipe to keep the heat down

kok328 04-27-2008 06:21 AM

By "pipe dope", do you mean plumbers pipe dope or is this a roofer's terminology for roofing tar?

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