BUILDING

PURPOSE:To make efficient interior heating possible by a method wherein the inside of a horizontal member supporting upstairs external wall panels is filled with heat insulating material. CONSTITUTION:A groove 1c is formed to the underside of a frame 1a of an external wall panel 1, and surface materials 1b are stuck to both sides. A top chord 4b and a bottom chord 4c are provided to a horizontal member 4 made from channel steel, and an erected piece 4a is provided to the upper face of the top chord 4b. Then, the front end of the erected piece 4a is put into the groove 1c of the upstairs external wall panel 1, and the panel 1 is supported with the horizontal member 4. The inside of the horizontal member 4 is filled with heat insulating material 6, and the attic 3 side of the horizontal member 4 is covered with an end rail 5. A cross rail 8 provided to the upper bed on the ceiling plenum 2a side is hung over the horizontal member 4 and the end rail 5 is fixed to the frame 1a with nails 7. Then, heat inside the downstairs is led to the upstairs floor through the ceiling plenum 2a without being dicharged to the attic 3a. Thereby, interior heating can be made efficiently during wintertime.