Expert: James Ball - 10/22/2008

Question
Dear Mr. Ball,

I've two fireplaces sharing the same chimney built in 1975. The lower-level
fireplace has a gap between the firebrick and the lined chimeny flue. The gap
is about 2 by 4 inches in size and is partially blocked by some kind of
material, perhaps a small piece of brick. My problems is this gap allows
smoke to filter through the chimney into the upper-level living space. Besides
the missing damper on the lower-level fireplace, everything else is fine.

My question is: What do you think of filling this gap with patch made for
fixing cracked firebricks? I'm not sure I can achieve this as the gap occurs
about three feet above the firebox and is difficult to reach. Big expensive
repairs are not possible in the present situation. Ideas?

Kind regards, --Barb

Answer
Hello Barbara, I would have a local Certified Chimney Sweep (www.csia.org, there you can look up by zip code to find one near you) take a first hand look at what you have. we have the tools needed to make this kind of repair, Chamber Tech, Smoke Tite...etc. "to just fill the crack" with out cleaning it properly I do not think the fill would stick and hold up over time or work at all.
do not use either fireplace until the problem is solved for your home and family's safety
James Ball