To endure even a strong earthquake by construction of the ridge, and to enable execution work in a short time.

This fixture is composed of a support tool 1 for arranging a rail 2 having a longitudinal directional opening part 3 in an upper part on legs 4 straddlingly fixed to a sheathing roof board, a joint nut 6 having on the lower end a slider 8 inserted into the rail, and having 7 having the leg parts freely movable in the opening part, a bolt 9 threadably attached to the joint nut, a presser plate 10 for arranging a cutout 11 for inserting the bolt on the front and rear ends and fixing a covering tile for gap between rafters, a lower nut 13 threadably attached to the bolt above the presser plate, a rafter presser 14 for fixing a rafter by being inserted into the bolt above the lower nut, and an upper nut 7 threadably attached to an upper part of the rafter presser. The covering tile for gap between rafters, a large ridge tile, and a ridge tile are fixed by the bolt, the nuts, the presser plate, the rafter presser, and the rafter, and since a channel tile with a collar on one end s fixed to the rafter by a nail, sufficient strength is provided, and the execution work is completed in a short time.