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Kwhord (Kwhord)
Senior Member
Username: Kwhord

Post Number: 201
Registered: 10-2006
Posted on Friday, April 03, 2009 - 12:26 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

US Heritage group is the best source for historic masonry information. We'll be sending one of our crews to get certified by them this fall. Until then, I'll leave the masonry repairs to someone else, with the exception of pointing the flashing we install.
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Kwhord (Kwhord)
Senior Member
Username: Kwhord

Post Number: 200
Registered: 10-2006
Posted on Friday, April 03, 2009 - 12:23 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Absolutely agree with the comments about the paint. The water has to escape somehow and the thirsty lime plaster walls are the next best place if it can't get out through the joints on the exterior. They were considering a new paint job but I talked them out of that last year thankfully.
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John_chan (John_chan)
Junior Member
Username: John_chan

Post Number: 20
Registered: 08-2006
Posted on Friday, April 03, 2009 - 10:38 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

The rubber doesn't look bad, but the pictures aren't quite close enough to see it fully. I think there's 4 different reasons why this could leak.

1) The rubber roof is not breathing, and it's condensating. It's like wearing a rubber glove.

2) The tops of the clay pots are open and the inside walls of the chimney could leak.

3) The crown is cracked and leaks through.

4) The chimney is painted!! Any moisture that gets inside can't get back out and it doesn't breathe. It could condensate, or any little cracks in the paint could allow water in and not let it back out. If they want a white chimney, they should limewash it instead of painting it. On these old chimneys, it's vital to use the correct mortars and limewashes. A good source of data would be the US Heritage website.

If it's a good size leak, it's most likely #3 or #4.
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Slate_man (Slate_man)
Senior Member
Username: Slate_man

Post Number: 389
Registered: 01-2007
Posted on Friday, April 03, 2009 - 05:43 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I also think you need to rebuild the top of the chimney, with a copper cap then reinstall the clay chimney pots.
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Old_school (Old_school)
Senior Member
Username: Old_school

Post Number: 105
Registered: 01-2009
Posted on Thursday, April 02, 2009 - 09:39 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

If you rebuild the top of the chimney and have the masons install a "drip" edge around the cap when they form it your problems will disappear. The rubber looks good and the saddle behind the chimney would preclude the water from coming on the back of the chimney. You willl not get condensation on the inner wall of the chimney so that would be a non issue. I think it is deffinetly the chimney cap.
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Kwhord (Kwhord)
Senior Member
Username: Kwhord

Post Number: 198
Registered: 10-2006
Posted on Thursday, April 02, 2009 - 07:49 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Ok here are the photos.

http://picasaweb.google.com/kwhord/ChimneyDamage#

The rubber is sealed on the corners and we didn't detect any moisture in the insulation by the corners where the greatest potential for a leak would be. The cap was cracked sometime over the winter because it was in-tact when we did the roof. There were several wind storms and an ice storm that could have caused the damage.

The paint bubble is at the transition of the wall and the ceiling on the left side and the "weep" marks are on the inside wall, across the entire back of the chimney. The rubber is retained at the top with the manufacturer's retainer bar as specified, and sealed as well. The flashing is pointed with lime putty mortar.
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Kwhord (Kwhord)
Senior Member
Username: Kwhord

Post Number: 196
Registered: 10-2006
Posted on Saturday, March 28, 2009 - 05:56 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I'll get photos, I should know better.
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Kwhord (Kwhord)
Senior Member
Username: Kwhord

Post Number: 195
Registered: 10-2006
Posted on Saturday, March 28, 2009 - 05:55 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I didn't paint the brick, for the record. I know better. The cap was cracked this winter when tree limbs fell. So it is a new issue. If I had seen a cracked cap when we flashed the chimney I would have recommended they call a mason to repair it also. Their old interior damage was definitely from a roof leak, I just don't think the current problems are being caused by the roof.
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Walter_musson (Walter_musson)
Senior Member
Username: Walter_musson

Post Number: 152
Registered: 07-2006
Posted on Saturday, March 28, 2009 - 03:13 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Kurtis,
There are times when only a true thru flashing will correct the problems - or if done while building the chimney ,prevent leakage.
Like Joe and John I'd have no way of knowing from here.
Condensation could be a cause too , but less likely.
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Old_school (Old_school)
Senior Member
Username: Old_school

Post Number: 96
Registered: 01-2009
Posted on Saturday, March 28, 2009 - 02:49 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

If the cap is cracked, why didn't you have a mason repair / replace the cap? Why paint the brick, why not fix it. Is there any "attic" space? Is it vented? That would be very important too. Is the bathroom vent vented outside or into the attic space? Like Joe says, we need pictures!
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Joe (Joe)
Senior Member
Username: Joe

Post Number: 391
Registered: 07-2006


Posted on Saturday, March 28, 2009 - 12:05 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Can you post a photo of the chimney?
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Kwhord (Kwhord)
Senior Member
Username: Kwhord

Post Number: 194
Registered: 10-2006
Posted on Saturday, March 28, 2009 - 12:01 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I need some help in determining a problem with a chimney that has been an on-going issue for a homeowner. Before we worked on the roof they had extensive water damage to the plaster at the ceiling around the chimney. This problem had been dealt with in the past by adding another layer of tar to the old metal roof every time a new water spot appeared.
In the fall we took up a metal roof that had been completely coated in tar and replaced it with EPDM. This is a very low-pitch maybe 1/12 or 2/12. The problem chimney is a triple flu chimney on an exterior wall. At the chimney, we ran EPDM 4" up for the base and counter-flashed with copper flashing.

After we did the roof the homeowner painted the room and now there are paint bubbles and "weap" marks on the wall from water. The "weap" marks look like a bathroom wall does after you take a hot shower. I think it could be a condensation issue. Would the wall around the chimney be colder, promoting warm air to condense first on the chimney before the other exterior walls? The chimney also has a cast-stone top and clay chimney pots. The top is cracked so I assume water can get in there. It is painted with latex paint on the exterior and except for the joints where we tuckpointed the flashing, all of the joints are painted so there's nowhere for water to escape from the brick once it gets in. In addition to this the chimney is on the north side of the house and the stack is blocked on the south by a room addition.

Just to be sure I'm going to take the counter flashing off and ensure that the corners where sealed properly but there's no damage to the plaster or staining like you would normally have with water entry from the roof.

What do you think about the condensation theory?

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