Having moved into a new home in the summer, we were surprised in the winter when our living room floor was cold to play on with our baby. There was a distinct draft coming from the fireplace. Had the flue been left open? No, it was the vent intake below the fireplace. A fan sucked in air below the fireplace and blew warmed air out above it, just below the mantle, presumably to make the fireplace more efficient.
I took the vent grill off below to look underneath, and, of course, there's nothing under there in terms of insulation. So how does one prevent cold winter air from guttering from this area? What was left off in contruction to cause this, or what has failed? I have no idea how to solve this or even who to call the fix something like this.