PURPOSE: To accomplish labor-saving of execution by fixing a pair of T-shaped fittings to the upper and lower sides of a vertical surface of a column, and fixing the end part of a horizontal beam material to a gap between the fittings.

CONSTITUTION: A pair of T-shaped fittings 4 comprising a base piece 5 and a hang piece 6 are fixed to the upper and lower sides of a vertical surface F of a column 2 formed by a square steel pipe by high tension bolts 7. The end part of a beam material 3 formed by an I-steel 3 and a spacer 9 are inserted in a gap G produced between the hang pieces 6 of the upper and lower fixed fittings 4 by bolts. Accordingly, the man hour of work in an execution field can be reduced so as to accomplish labor-saving of execution.