“Chimney Onion” Insulation retrofit
Poot_Klopp
| Posted in General Questions on
Here is an interesting insulation problem. This is a rather large decorative chimney, behind it is the smaller actual chimney. The small one exhausts a steam boiler and hot water heater with an installed liner.
What, if any, would be the best way to insulate the void between the two? Would you insulate it?
Attached pictures for reference. The void pretty much connects the basement (balloon framing) to the second floor floor joists.
Home exterior is vinyl, 1″EPS, original wood siding, craft paper, board sheething.
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Replies
You have to leave a 2" or larger gap around chimneys in most cases, so I would not try to insulate the entire space. I can't recall seeing a chimney built like that before--very interesting, and not easy to deal with.
I can't think of an effective, inexpensive solution. The most straightforward solution would be to upgrade to direct-vent appliances and remove the chimney entirely, but that's probably not in your budget. The "right" answer is probably to demolish enough interior walls that you can frame new walls around the functioning chimney, maintaining a 2" gap, and insulate those walls.