I have a new house with a gas fireplace. My problem, a very large draft coming from the top and bottom vents and sides of the fireplace making the room very cold. I spoke to the fireplace contractor and was assured that the firebox is sealed so the draft is not originating from the vent stack. The unit is framed around what is commonly referred to as a "dog house" or "bump-out" . I know the three walls of the bump-out were insulated and poly wrapped because a checked this before sheet rocking began. However I am not sure if a ceiling was constructed inside the bump-out which would allow for ceiling insulation. I think cold air is entering from the soffit of the bump-out and because there is no ceiling, entering the room from around the gas fireplace. What do you think, does this sound logical? If so how can I check for insulation in the ceiling of the bump-out? Thank you GTA
Yes, you should be concerned, there is no reason for a draft to enter the house at a fireplace. This situation could also allow for moist interior air to penetrate into some of the wall structure and cause some moisture problems.
Without a site visit it will not be possible to tell you the exact nature of the problem, but I would urge you to bring in a expert who can analyze this situation and see if there are other similar problems in the house. This sounds like a framing problem and you need to make sure that who ever made this mistake didn't also make some other mistakes.