A damper seals off your fireplace from the outside elements. However, it must be open when a fireplace is in operation. Often they are left open, or they no longer seal correctly and air gets in, but more importantly….heat gets out. Having a broken or improperly sealed damper on your chimney is allowing valuable heating dollars to float out of your home. We can install a top mount damper on masonry fireplace or a blade damper (in the throat area of the firebox above the back firewall) in a masonry or retrofitted fireplace. Factory built fireplaces use a different damper than a masonry fireplace. Top mount dampers are not UL listed with your factory built fireplace or Class A retrofitted flue pipe system and they should not be installed.