| 摘要 |
PROBLEM TO BE SOLVED: To provide an opening building material that makes an internal appearance good and that prevents retention of dew condensation water.SOLUTION: An opening building material includes a frame 1 and a sash 2. The frame 1 has indoor side frame parts 11, 12, 13 and 14 on an indoor side inner peripheral part. The indoor side frame parts 11, 12, 13 and 14 have an inner peripheral side surface 35 provided with a protruding piece 28 protruding to an outdoor side. The protruding piece 28 is positioned on an inner peripheral side with respect to stiles/rails 15, 16 and 17 of the sash 2. A gap 32 is provided between a tip of the protruding piece 28 and a glass surface 31 of the sash 2. |
