insulating fireplace gas insert

Feb 09, 2007 3 Replies

Our fireplce gas insert always has this cold draft coming out of it when not in use. The flue damper was removed when installed. The insert is feed by two three inch pipes. I have been told to stuff some insulation up the flue to seal it up. Roxul safe and sound was mentioned. Itd seems to be very fire resistant.



Is this a normal thing to do? I was told the installers should have done it.



Do you need the chimney? If not, have someone come in and block off the top. Alternatively, pull the unit out and install a rigid board of polystyrene or polyurethane and spray foam the edges for a tight seal. I am assuming with this last suggestion that the unit is zero clearance. Others more knowledgeable may want to comment on any fire safety issue here.

If you are looking to plug a fireplace flue I would think a chimney plug would be the route to go. There is something called a chimney pillow at

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that should do the trick.

No. The chimney is still sort of used. There are ducts running in it, for the direct vent fireplace insert.

I just am leary of stuff> If you are looking to plug a fireplace flue I would think a chimney

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