Is it OK to have a chimney cap much larger than my flue?

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JohnInVA

New Member
Feb 25, 2021
1
Roanoke VA
My situation is that my flue is flush with the crown and needs a cap added to it. I think similar homes in the neighborhood that have a double flue cap look better due to the cap being closer to the shape of the chimney (the chimney is 56-3/4" x 16.5", while the flue is ~8" x 4"). So I was thinking to get a 28" x 9" chimney cap for aesthetics, since I will need to screw/glue it onto the crown anyhow. Does anyone see a problem to doing this? I'm worried that a larger cap will dissipate heat faster, possibly resulting in more build-up (a concern since I will not be able to remove the cap to clean, unless they disassemble(?)). Thanks!
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
26,926
central pa
My situation is that my flue is flush with the crown and needs a cap added to it. I think similar homes in the neighborhood that have a double flue cap look better due to the cap being closer to the shape of the chimney (the chimney is 56-3/4" x 16.5", while the flue is ~8" x 4"). So I was thinking to get a 28" x 9" chimney cap for aesthetics, since I will need to screw/glue it onto the crown anyhow. Does anyone see a problem to doing this? I'm worried that a larger cap will dissipate heat faster, possibly resulting in more build-up (a concern since I will not be able to remove the cap to clean, unless they disassemble(?)). Thanks!
We install them all the time and it is very uncommon for them to cause any issues at all. And yes the top usually pulls off with a few bolts. I wouldn't buy one that didn't
 
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