Chimney leaking bad... Advise needed
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Chimney leaking bad... Advise needed
Serious water still leaking down the chimney and into the attic. The roof is new, all the flashing is new, the chimney cap is new, and most of the cement between the bricks was repointed.
A leak test was recently performed using a garden hose. The shingles and the area of the side flashing up to the brick line tested dry.
When the water was directed further up onto the bricks, the water began seeping as evident in the photo. It took awhile but eventually it became serious.
1. Are the joints between the cement and the bricks still allowing water to penetrate?
2. Can the bricks being porous?
3. Will a good quality sealant fix my water problem? Any product recommendations?
A leak test was recently performed using a garden hose. The shingles and the area of the side flashing up to the brick line tested dry.
When the water was directed further up onto the bricks, the water began seeping as evident in the photo. It took awhile but eventually it became serious.
1. Are the joints between the cement and the bricks still allowing water to penetrate?
2. Can the bricks being porous?
3. Will a good quality sealant fix my water problem? Any product recommendations?

#2
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I would thoroughly inspect the flashing and roof shingles again and pay particular attention to the top of the flashing where it meets the brick. Also look for a nail hole in the shingles. Sometimes roofers drive a nail through for mounting scaffolding or they slip with the nail gun. A nail hole is difficult to spot but can let in a surprising amount of water. It is also possible that the leak was occurring when you had the hose aimed down lower but was slow enough that it was not noticed until you had moved on and were spraying water higher up. Be vigilant and don't give up until you find the leak. It's better to fix it now than let it go and have to repair rotted wood.
Yes, the bricks and mortar will absorb water but they don't let it pass through at anything but a glacial pace. You would never see a leak inside the house from it. The water must be coming in from a small crack or gap somewhere.
Yes, the bricks and mortar will absorb water but they don't let it pass through at anything but a glacial pace. You would never see a leak inside the house from it. The water must be coming in from a small crack or gap somewhere.
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Pilot Dane: I understand what you are saying however we ran copious ammounts of water with the garden hose for at least 1/2 hour on all sides of the roof line and base of chimney going out 3 feet in every direction. No water leaked into the house. Waited 30 minutes to be sure then began saturating the bricks/motar. It did not take long, the water begin to migrate into the attic cinder blocks.
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i would say if it was a mortor leak you would see the mortor missing...look closely at the top of the flashing for a rust through or a gap between it and the brick or if you have flashing that is shaped (at the top) like a > look to see that a brick has not chipped above the > and is letting water run down the brick and then back behind the flashing
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have you checked your chimney cap? Do you have a chimney cap above your last course of brick? If so there should be flashing attached to the flue that comes down under cap and on top of last course of brick. i would check the cap and see if it has lost its bond and also check the flashing where it meets the flue to make sure there is a good seal.
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I'm happy to report the water problem has been fixed. The chimney was the problem. After re-pointing the motar, 2 thin coats of Geocel were applied to the motar, chimney cap, and all cracked bricks. Note: After the re-pointing water still seeped into the attic. After 2 coats of Geocel, problem sloved. IMO, this is one amazing product.

#8
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I am glad you found the source of the problem. With all my rental houses I tear down un-used chimneys below the the roof line whenever possrces.ible. They can be annoying leak sources.