Abstract: A building module is formed of a first plurality of isosceles triangular members forming a roof and a second plurality of isosceles triangular members forming walls which support the roof. In one embodiment, some of the triangular members are right triangles and each of the remaining triangular members have two sides which are three-fourths the length of their third side. In another embodiment, all the triangular members each have two of their sides equal in length to three-fourths the length of their third side. Also, each of these embodiments can be combined to produce larger units and can be combined with a partial cubical form to provide vertical walls.

Abstract: A structural form is constructed of a single sheet of material, such as cardboard, which is cut along certain lines and folded to provide a three dimensional configuration. The sheet material is cut to provide tabs each extending from a side of a respective panel portion. The panel portions, when folded, form the outer side walls of an enclosure. The tabs at opposite edges of each panel are folded into the enclosure to form channel members. Every alternate one of the tabs is provided with additional perforations, such that it can also be folded to nest an adjacent tab when all of the tabs are folded inwardly of the side wall panel portions. The tabs are folded such that a first portion thereof, which is secured to its respective panel portion slopes inwardly and toward the center of the enclosure. The remaining portion of each tab is folded to extend from a central area within the enclosure to a respective one of the panel portions.