Abstract: An efficient zero clearance fireplace, space heater is disclosed which is adaptable for installation in either mobile homes or permanent structures. The fireplace unit consists of a stainless steel firebox with an opening for access to the interior thereof. The firebox is surrounded by a first metal skin spaced therefrom which mounts glass doors across the opening. The outer surface of the top, bottom, sides, and back of the first skin are sheathed with an insulating felt. A second metal skin surrounds the first on the sides, back, and top. Outside air is circulated between the firebox and first skin, and heated thereby as the sole source of combustion air. This heated air is also circulated into the room through vents in the front of the first skin. Cool room air from the floor circulates upwardly between the first and second skins only to cool the unit. An optional damper and combustion air control is provided.