The components connecting the various parts of a building are standard-sized, materially homogeneous elements. Building loads, deflections and thermal expansion rates, however, are non-uniform and distributed in a heterogeneous manner. Using material evenly in effect is inefficient and increases embodied energy and componentry manufacturing, transportation and installation costs. The project aims to catalogue the metal components used in structural framing and curtain walling systems in buildings. These are then redesigned using topology optimisation. This CAD method is based on simulating support and loading conditions and calculating the corresponding optimal material distribution, effectively minimising the amount of material in a part. The total material, weight, cost, embodied energy and pollutant emissions of the conventional and optimised components are calculated, and the figures compared. The project consolidates and adds to the sparse building component optimisation research, in the form of a taxonomy of optimised buildng parts.