Abstract: Forced air space heating fireplace having a metal casing defining a combustion chamber with an opening facing a room to be heated. Air flow tubes are provided beneath the floor of the combustion chamber and at the top, the air flow tubes being interconnected by lateral air flow tubes then lying outside the casing. The interconnection is such that the tubes form a continuous air flow path having an air inlet connected to a blower, which draws fresh air from outside the room to be heated, and two air outlets disposed laterally of the casing and opening into the room to be heated. In one form, the lateral flow tubes are encased in an insulating brick construction. In an other alternative, they may be contained in a jacket surrounding the casing and also including the top air flow tubes.