What to Do With My B-Vent Gas Fireplace That Leaks A Lot of Air?

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New Member
Mar 13, 2019
Ontario, Canada
Hi All.
I have an ugly B-Vent (Natural Vent) Gas fireplace that previous owners installed (plopped) in what used to be a woodstove. Behind the stove there is metal sheathing, behind that is the brick chimney area. I am wanting to make things more efficient and air tight. There is currently cold air escaping behind the built in shelves (I suspect it is coming from the brick chase/chimney). Of course the metal sheathing behind the stove isn't insulated at all and gets cold to the touch in cold weather. It's just an efficiency nightmare.

20190313_080326.jpg The area behind the stove is where the sheet metal is which seals off the stove from the chase area.


Buying a new direct-vent fireplace isn't in the cards at the moment, hopefully down the road.
For now, what would be my best option?

-Should I seal up/insulate the chase where it meets the house as best as I can and remove the fireplace?
-If keeping the fireplace is an viable option, is it safe to add rigid insulation into the brick chase area? Do chimneys get hot from a gas fireplace?

We do use the fireplace a fair bit - however, I suspect part of the reason we feel we need it is due to all the cold air that is leaking in. Our main floor feels kind of chilly even with our furnace set to 23 deg. At 23 we should be very cozy. Windows and attic insulation are not the issue.

I like the idea of having a fireplace, if nothing else for a backup heat source if the power goes out or our furnace quits but having a 4" hole letting air into my house plus a 2x2 uninsulated piece of sheet metal in my wall isn't doing me any favors at the moment.

Look forward to hearing your suggestions!