Effect of Changes in Layout Shape on Unit Construction Cost of Residential Buildings
The shape of a building layout is the spatial attribute that defines the outline of the building. It affects the areas and sizes of vertical components such as external walls and associated finishes, windows, partitions and associated finishes, etc., as well as the perimeter detailing such as ground beams, fascias, and the eaves of roofs. The conclusions of previous studies on the cost implication of building shape have been premised on the knowledge of building morphological and geometrical characteristics, and have lacked empirical authentication. This study used empirical data to investigate the effect of layout narrowness and complexity (irregularity) on total and unit construction costs. The data used is the Saudi Arabian ‘typical villa' as the base case at current prices and other variant shapes. The results of this study indicate that perimeter-to-floor ratio, unit construction cost and overall project cost are affected by variation in plan shape narrowness and complexity (irregularity). These results will assist construction professionals, especially the cost consultants, in making more objective design decisions and in giving cost advice related to plan layout for the benefits of their clients.
Samaru Journal of Information Studies Vol. 7 (1) 2007: pp. 24-31