Expert: Bart Ogden - 4/21/2008

Question
QUESTION: I have a home that was constructed 7 years ago.  It has 3 masonry chimneys, all of which have been leaking from the day one.  All of the chimneys have terra cotta flue liners and they do not vent any appliances.  In all three chimneys, leaking occurs around the hearth and at ceiling just in front of the firebox.  Two of the chimneys have large terra cotta chimney pots with birdcages.  In these chimneys there is leaking inside of the flue liner with hard rains.  The other chimney has a flue cover and usually does not leak water inside the flue liner unless there is a hard rain.  All have a poured concrete cap that overhangs ~ 2 inches.  There is not a drip edge on the caps.  I have spent over $25,000 making various repairs.  The flashing has been repaired twice and I believe the most recent repair was very good.  Water testing was performed around the flashing without leaking inside of the house.  The chimney caps have been inspected and are in excellent condition.  We sealed the outside brick with a standard approved masonry sealant.  We have inspected the outside brick and minor tuckpointing repairs were completed.  No leaking occurs in the winter, only with rain.  One thing I did notice is that the terra cotta flue liners do not line up perfectly; I can see some overlapping when I look up into the liner.  I wonder if water could be wicking from inside the liner to the space between the liner and brick/cinder block??  I am quite desperate to solve the problem.  Any thoughts?

ANSWER: Hi Paula,

Thanks for the question.

This is something that I would recommend you contact a local CSIA Certified Chimney Sweep to do some on-site diagnosis of your problem.  It's really not anything I can diagnose over the internet for you.

You can find a CSIA Certified Chimney Sweep at www.csia.org.

Thanks for using AllExperts.Com and good luck with your project.

Sincerely,
A. Bart Ogden, President
Home Safe Hearth & Chimney, Inc.
Wichita, KS
Voice: 316-265-9828
Fax: 316-265-9890
www.homesafeks.com


---------- FOLLOW-UP ----------

QUESTION: Thank you for your response.  I did have a CSIA chimney sweep out last fall and thought it was the flashing which has been repaired.  However, they were reluctant to inspect all of the chimney crowns because of the location and height of the chimneys.  I have a mason scheduled to look again at the crowns, but I am still skeptical that the leak can be found.  Do you think that if water travels down the inside of the flue it can wick to the space between the flue and cinder block/brick face.  If so, can it travel down and come out at the ceiling.  In addition to the ceiling, water is leaking behind the fireplace surround.

Answer
Hi Paula,

If the flue is intact, water should be channelled down to the smoke shelf area where it can make its way out into the firebox.

If the flue has offsets and is not intact, water can get out into the structure and can then show up in many places, including those you've described.

You could have the chimney video-scanned for integrity, but I would have the tops looked at carefully for water coming down the flues.

If it's raining 2" out in the yard, it's also raining 2" down that flue.

If the 2" crown does not have a relief groove cut in the bottom of it, water can run over the edge and wick right back into the structure.  Make sure that area is checked carefully.

Sometimes water leaks take a while to chase down, you'll just have to stay at it.

Thanks for using AllExperts.Com and good luck with your project.

Sincerely,
A. Bart Ogden, President
Home Safe Hearth & Chimney, Inc.
Wichita, KS
Voice: 316-265-9828
Fax: 316-265-9890
www.homesafeks.com