Venting through roofed off chimney

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New Member
Feb 13, 2019
I did a pop top addition a few years ago and am now looking to re-finish my basement. There is an old wood burning fireplace down there, but the chimney was cut off and roofed at the top of the first story during the renovation.

I would like to put in a direct vent gas insert. Can I punch through the side of the chimney and side vent with flex pipe? There is a walkway there. So I have to vent 7’ up. Which would mean the pipe would have to run about 14’ vertically before the horizontal termination.

Is this doable?
I'd talk to a stove dealer and see what they can suggest. I wouldn't be at all surprised if some or perhaps many gas fireplace inserts would allow that kind of direct vent termination. After all, it's quite common for direct vent installations to terminate through a roof -----what you are proposing is just extending the distance before making a 90 degree turn to exit out the side of a house.

But what you can do requires that you look at the directions for venting a particular fireplace to be sure that what you want to do is permitted. That will be laid out pretty clearly in the installation manual for the fireplace. So that's what you should consult.

A fireplace shop sales rep should be able to help you with that.

If you want to specify the make and model of a fireplace insert that has caught your eye, perhaps we can find the manual on line and check it to see what it says.