In an opening roof, particularly designed for greenhouses, sheds and the like having at least one pitch (1) pivotably supported at the lower edge thereof at a stationary fulcrum (4) on a bearing structure (5), said stationary lower fulcrum (4) is constituted by a type of rocker bearing or knife-edge bearing which is formed for example, by the top edge of an upright web (12) fixed to the bearing structure (5) and bearing an inverted V-shaped or U-shaped portion (11) provided at the lower edge of the roof pitch (1), or vice versa.
