Assembly system for roof structures

摘要

The structure comprises parallel joists (1) of I-section and between which are rafters (2) at right angles to them. At each connecting point between the rafters and joists there are two hooks (5, 6) open to the top on the vertical joist web (3) and protruding beyond the joist flange. The top hook (5) comprises two parallel first ones (8) spaced apart, and the bottom one a single one (9) or two parallel ones between the vertical planes defined by the top hooks. On the rafter end face (4) is a flat component parallel to the joist web, and containing vertical slots (12, 13) open to the underside for engagement by the hooks, the rafter being inserted from the top.