| 摘要 |
PROBLEM TO BE SOLVED: To prevent creaking sound by butt-fixing the end parts of ceiling boards forming a pair of parallel sides of a ceiling face to wall surfaces through cushioning material, and bulging the center part of the ceiling face upward to form approximately arched shape. SOLUTION: A plurality of hanging members 34 are provided at an upper part between a pair of wall surfaces 30. A ceiling joist 32 is fitted to the lower end parts of the hanging members 34, and a plurality of ceiling boards 12, 14 are provided to form a ceiling face 10. The center part of the ceiling face 10 is bulged upward to form approximately arched cross section, and end parts 12a, 16a of the ceiling boards 12, 14 forming a pair of parallel sides of the ceiling face 10 are butt-fixed to the wall surfaces 30 through cushioning material 20 formed of long-sized members made of hard rubber or the like. The ceiling boards 12, 14 are formed of plywood, and the surface of plywood is covered with a lamination layer. A pair of parallel end parts jointed to the other ceiling boards 12, 14 are provided with tongues and small holes so as to be jointed by tongue and groove. Creaking sound can therefore be easily prevented while maintaining arch shape. |
