Abstract: A rigid housing module is formed of a plurality of module walls connected to one another at a predetermined angle other than 0.degree. and 180.degree.. Each module wall has an assembly of identical planar structural elements each having the shape of a trapezoid. Each element has a relatively long inner side, a relatively short outer side and two diagonal sides constituting, respectively, the long and short bases and the two non-parallel sides of the trapezoid. The elements of each assembly are arranged in a juxtapositioned series wherein all inner and outer sides are parallel to one another and wherein adjoining elements are connected to one another alternatingly along adjoining outer sides and along adjoining inner sides and further wherein the elements are oriented at a predetermined oblique angle with respect to an inner assembly plane in which the inner sides lie.