Abstract: A conventional fireplace opening is closed off by a flat steel plate the size of which will cover conventional fireplace openings. Two clamps permit the plate to be secured to the fireplace lintel. A firebox is bolted to the front of the plate so that it is located entirely within the room, rather than in the fireplace opening. An access door is provided at the front of the firebox, and a draft opening below the door provides control of inlet air to the fire. A damper valve is located in an exhaust opening at the rear of the firebox to provide control of the products of combustion within the firebox.