The document proposes several low-cost construction techniques including using funicular shell roofs, geodesic domes, A-frame structures, interlocking hollow concrete blocks, soil cement blocks, and rat-trap bond wall construction. It suggests optimizing designs to reduce materials and costs for foundations, walls, doors, windows, and lintels. Foundations can use rubble masonry with bond stones instead of concrete beds. Wall thickness and rat-trap bonding can reduce brick usage. Concrete blocks and soil cement blocks provide savings over burnt bricks. Alternative materials can lower costs for doors, windows, and lintels.