I place a roll of fiberglass insulation in the base of the chimney to keep the cold air out. The commercial damper systems are not air tight. The heat from the pipe actaually fuses the glass over time and I replace it yearly.

I LIVE IN A 2 STORY CONDO TOWNHOUSE. I HAVE A ZC PREFAB FIREPLACE. I WANT TO INSTALL A WOOD BURNING INSERT, HOWEVER I NEED ONE SMALL ENOUGH TO FIT. I FOUND A HAMPTON INSERT THAT ACCEPTS A 15 1/2 DEPTH. HOWEVER, THE HEIGHT IS 19 1/8. WHEN MEASURING HEIGHT DO I MEASURE FROM THE FRAME AROUND THE FIRE PLACE THTAT THE DOORS ARE CONNECTED TO, OR FROM THE FLOOR. IS THAT FRAME AROUND THE FIREPLACE REMOVEABLE? IF SO I HAVE THE HEIGHT NEEDED TO GET AN INSERT PUT IN. I WAS TOLD THAT THE TOP PART WITH THE DAMPER KNOB WAS NOT REMOVABLE BECAUSE IT IS PART OF THE UNIT.