chimney through conditioned attic
sorethumbs
| Posted in Energy, Heating & Insulation on
I have a question, I need to install a stainless, insulated woodstove flue through a conditioned attic and out through a roof with sprayed foam insulation on the underside. Normally, you would leave a gap around the flue where it exits the roof for clearance. If that is done in a conditioned attic that would be leaving a huge hole in the envelope and compromise the whole purpose. My question is, how do you run the flue and keep the attic relatively airtight? Can you fill the gap around the flue with fire stop foam? Or stuff it with fiberglass insulation and accept the compromise? Your expert advise is greatly appreciated.
Replies
Just build an insulated chase around the chimney pipe.
This is a matter for the chimney manufacturer to answer. There are zero clearance and close clearance products out there. Everything should be written up in the installation instructions.
In my case I've got a chimney going directly through a 2X6 pine ceiling. The wood is tight against the square steel chimney.
A sheet metal collar can seal the inside. The flashing on the outside. And in between ... fire rated insulation. Rockwool might work, but I think there are products out there for this. Talk w/ your local HVAC installer. Also the building official (are you getting a permit?).
Also the stove mfg should give you some information on how to do this as well ... as another poster elluded to.