Abstract: A generally pyramidal structure is formed by a plurality of sloping sides with adjacent sides abutting along a ridge joint which intersects a common vertex. The pyramid is truncated, thereby creating an opening transverse to one ridge joint and extending through the two adjacent sloping sides. The opening typically is closed by a vertical structural element. This pyramidal building design can be applied to structures of different sizes from small collapsible shelters, as substitutes for tents, to permanent buildings having multiple stories and/or adjoined units. The basic embodiment of this design has four oblique quadrilateral panels which form triangular openings along opposite ridges.