Back to Back Fireplaces into See Through Gas Insert?


New Member
Oct 18, 2020
Boston, MA

I was researching putting in a gas fireplace insert into one of my fireplaces Turns out the fireplace only has a depth of 13 inches which really limits my options. Between the depth of the insert I also need room for the gas line. I got an estimate and the price was up over $8,000, and there still not sure if they can do it because the flue at the top of the chimney is only 6x6.
This got me thinking about how I have to back to back fireplaces with separate flues. I am wondering if it is possible to convert these two fireplaces into one see through with a gas insert. Also the flue liner for the other chimney has a lager diameter flue.
So I am wondering if this is doable, and if so is it a complicated expensive job?

Thank you!



Patriot Guard Rider Moderator
Staff member
It NOT doable in the manner that you want to do it.
There are not "See Thru" inserts available at this time.
There ARE see thru Fireplaces, but that installation requires
total removal of all the masonry structure in there,
& reframing an interior chase for the venting...
That being said, you have the option of having a gas insert
installed which has an extended return on the surround.
This return can add 3-4 inches to the depth & leave plenty
of room for gas line. It will bring the unit further out on your hearth,
but the look really doesn't look too bad.
A 3" flexible aluminum colinear liner kit
will fit in a 6x6y flu tile. It'll be tight, but it will work. I have done it.
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