Abstract: A lattice girder (11) has an upper chord (12), a middle chord (13) and a lower chord (14) between which stiffening struts (15, 16) extend. Furthermore, at least one piping groove (17, 17', 18, 18') is provided at the middle chord (13) at at least one side of the lattice girder (11) and extends parallel to the longitudinal extent. The pipings (19) of the tarpaulin(s) (20, 20') are drawn into the piping groove in the longitudinal direction. In acchordance with the invention two piping grooves (17, 18; 17', 18') are provided above one another at at least one side and preferably on both sides of the middle chord (13).