12x12 flue to large to draft?

12x12 flue to large to draft?

PostBy: speerstra On: Mon Jul 21, 2008 9:30 pm

Hi Guys,
Getting a LL hearth for a 12"x12" rectangular terra cotta chimney. The chimney is 13 feet tall. I am concerned about the draft. The question is do I need to line it since the diameter of the flue is so large?
Thanks...
speerstra
 

Re: 12x12 flue to large to draft?

PostBy: speerstra On: Sun Jul 27, 2008 11:51 am

Guess I answered my own question. Had a chimney sweep do an inspection. Flue looked fine but he said I definitely need a liner. He doesn't install/sell them so it isn't in his interest to give me a bogus answer. Posting on http://chimneysweeponline.com/holinst.htm indicates "Code prohibits venting any woodburner into a chimney flue with a cross-sectional area (CSA) that is more than three times the CSA of the flue collar on the stove. Thus, if your stove has a 6" flue collar (28 sq.in. CSA), the chimney flue must have a CSA less than 84" (3 x 28). "
speerstra