Abstract: An arch element (1") for protecting roofs has at least one tubular arch (2) held in the curved state by at least one brace (4). The ends of arch and brace (2, 4) are interconnected by end connectors (3). In order to keep the brace (2) out of the direct connection between both end connectors (3) and to guide it along the arch (2) at a certain distance thereof, a flat connecting part (5) is arranged between and joined to arch and brace (2, 4). By using three arches (2), two braces (4) designed as bracing booms, four fabric or plastic connecting surfaces (5) that join the braces (4) to the arches (2), and three spacers (10) that keep the outer arches (2) apart, an unsupported, dimensionally stable three-dimensional arch element (1") is obtained that may be used directly as a shade or associated to other arch elements to carry roof surfaces. By using arches (2), spacers (10) and end connectors (3) that can be plugged into each other, the arch element (1") may be dismounted.