wet sheathing near chimney

[John Dirks Jr]

We all have found wet sheathing near the chimney I'm sure. The first thing that comes to mind as the cause is bad chimney flashing. To expand the possible culprits for the leak, what about cracks in the crown of the chimney?

Think about a chimney built with blocks. It has a brick veneer only on the portion above the roof line. Could water get in through cracks in the crown, run down between the block and brick and then be absorbed by the sheathing at the roof line?

[hausdok]

As you become more experienced, you'll realize that leaking flashings causing water infiltration are less common than cracked/deteriorating stacks that are allowing water in.

OT - OF!!!

M.

[John Dirks Jr]

So what are some ways of determining if wet sheathing is caused by either? Lets say the visible portions of flashing look sub standard and there are cracks in the crown. Are there reliable ways determining the source? Do you sometimes just have to say, "could be either or both"?

[David C. Argabright]

Wrap the chimney cap with a waterproof tarp. If the sheathing is still wet after rainy weather it's the flashing. And it could also be the cracked cap, flues, mortar joints, and soft porous brick. I don't think there's a magic bullet for this type of water intrusion.

I looked at the house with this same problem three weeks ago. Because of the wetness a new roof had been installed and the flashing had been redone twice. Three roofing contractors and two general contractors had taken a look. None of them were certain about the cause and each seemed to blame someone else. The last contractor that installed the shingles blamed the chimney brick and crown.

I had a specialist that I know pretty well take a look and he seemed to think the primary cause was the improperly installed valley flashing that ran very close to the chimney.

So.....back to the roofing contractor and the legal types I guess.

[Phillip]

Did the flashing look like this?

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Roof is two years old.

[John Dirks Jr]

Wow! A valley directing water right to the chimney. Now that's friggin brilliant! I wonder who gets the credit for that trouble free design? Was there some kind of an addition that led to that or was that the original design?

[John Dirks Jr]

Originally posted by David C. Argabright

Wrap the chimney cap with a waterproof tarp. If the sheathing is still wet after rainy weather it's the flashing. And it could also be the cracked cap, flues, mortar joints, and soft porous brick. I don't think there's a magic bullet for this type of water intrusion.

I looked at the house with this same problem three weeks ago. Because of the wetness a new roof had been installed and the flashing had been redone twice. Three roofing contractors and two general contractors had taken a look. None of them were certain about the cause and each seemed to blame someone else. The last contractor that installed the shingles blamed the chimney brick and crown.

I had a specialist that I know pretty well take a look and he seemed to think the primary cause was the improperly installed valley flashing that ran very close to the chimney.

So.....back to the roofing contractor and the legal types I guess.

So you see my point. It's easy to see the evidence of water penetration near the chimney. It's not always easy to determine the exact cause.

[hausdok]

Originally posted by AHI

So you see my point. It's easy to see the evidence of water penetration near the chimney. It's not always easy to determine the exact cause.

And you're not required to determine the exact cause. It's the job of whichever specialist comes out to look things over to determine what's causing it and to repair it.

The job is defect recognition. You see wet sheathing and lousy flashings, you can state that you think the leak is coming from the flashings but you might be wrong - especially if you didn't bother to examine the crown as well. You see a crack in the crown, you can state that the water intrusion might be coming from the crown, but, again, you might be wrong, 'cuz it might have come in through the flashings. If you can tell what caused it at a quick glance, fine, otherwise, identify the issue, explain why it's bad for the home, suggest a course of action, and move on; don't hang around trying to be be a house whisperer.

ONE TEAM - ONE FIGHT!!!

Mike

[Phillip]

Originally posted by AHI

Wow! A valley directing water right to the chimney. Now that's friggin brilliant! I wonder who gets the credit for that trouble free design? Was there some kind of an addition that led to that or was that the original design?

There is a sun room that was added on. The bad thing is I see this 2 to three times a year.