Some topical aspects of geometric modeling of technically effective forms of building products of mass industrial production - coatings of buildings and structures, as well as load-bearing elements of their frame, - composed of ruled shells of double negative curvature - a hyperbolic paraboloid and a conoid - are presented. The author's technically effective solutions for the structural organization of these objects are presented, having a regular discrete construction based on a small number of standard sizes of modular curvilinear shells, and reflecting promising directions and trends in their design shaping.