 The Gothic rib vault was one of the essential elements that made possible the great height and large windows of the Gothic style.Unlike the semi-circular barrel vault vault of Roman and Romanesque buildings, where the weight pressed directly downward, and required thick walls and small windows, the Gothic rib vault was made of diagonal crossing arched ribs.These ribs directed the thrust outwards to the corners of the vault, and downwards via slender colonettes and bundled columns, to the pillars and columns below.