The influence of the building shape on the costs of its construction

The choice of a particular architectural solution when designing a building considerably influences the costs of its construction. The aim of this paper is to present the indexes which may relate to the complexity of the building shape, and which were then specified and compared on a particular example. The article analyses various indices of building shape evaluation, their influence on the changes in construction costs and their sensitivity to the changes in the dimensions of the building. The methodology adopted in this article concerns the analysis of the selected simple factors assessing the shape of the building against the cost-effectiveness of constructing the basic elements of the building. The authors established the best building shape in relation to the costs of constructing the walls and foundations (square), and to the layout of the inside of the building (rectangle). They believe that the best evaluations of building shape were achieved by the LBI index, which evaluated the shape correctly in all of the analysed examples and which is the most sensitive to the changes in building parameters in correct proportions to the changes in construction costs. The article presents the indexes which may relate to the complexity of the building shape. The authors established the best building shape in relation to the costs of constructing. The authors provide the degree of the floor area usability in buildings of various shapes.