My corner fireplace doesn't have a chimney but instead a pipe going through the ceiling, attic, and roof and an insert that overhangs the high brick hearth. Currently there is a mirror above a too high mantel but when I tried to remove the mirror, there were two square holes, 1'sq, on each side of the fireplace. The holes were filled in with insulation but otherwise the mirror is their cover. Directly below the holes on the hearth part, near the floor, are two grates/vents the same 1'sq. I took the grate off and there is some kind of shiney silver covering over these holes. I have to do something with the mirror since it is at ceiling height and the vents below look horrible as well. The overhang of the insert isn't a huge problem and one that I could leave if I could do something about the holes. I would love to have the fireplace torn out and rebuilt complete with a chimney but the cost will be too much for a mostly decorative fireplace. We used it twice last year but it did heat the entire home. I don't want to tear out the fireplace due to the warmth it does give the room visually and without it, the weird angles of the room. So any ideas on what to do with the holes? I am completely stumped!