Building-up planning holds a prominent position within the planning- and realization process due to its closeness to the constructional-spatial translation. Based on spatial analysis, spatial characteristics and the elaboration of marginal conditions of spatial development within the framework of building-up planning, building volumina, building density, manner of building-up and storeyheights amongst others are to be defined and analyzed as to their spatial impact prior to their realization. The present project has presented possibilities for improvement of planning quality as well as of optimizing clearness and comprehension of the legally binding marginal conditions of building-up planning. Based on the wording of the Austrian Law governing Area Planning building-up planning constitutes an integral part of Urban and Regional planning. Building-up planning is the planning instrument considered right next to putting into reality the effects of which becoming immediately visible in the constructional transfer of frame conditions of spatial development. As a legal instrument it is - due to its overpacked nature - complicated in its practical application and disposes of only a small degree of flexibility concerning its consequences. Thus, a major goal of the research project aims at the development of a building-up plan of a prohibitory - (mandatory) plan acting as an instrument for designing public space.