The planners cannot go out today from a tabula rasa situation anymore. Environmental and sustainability issues have already formed the public idea that a 'greenbelt' of our cities is necessary, a kind of fortification leading to intensive development in towns inside a clearly delimited area within the surrounding nature. Since building on the periphery is limited, and the existing built substance has a certain cultural, architectural or at least environmental value, upgrading of existing buildings gains more and more ground from the design of new buildings. Masonry has been already...