Evaluating extended land consumption in building life cycle to improve land conservation: A case study in Shenyang, China

This paper aims to evaluate land consumption caused by materials flow in building life cycle for feasible land conservation measures in China. As distinct from the land occupied by buildings, extended land consumption was defined as lands consumed during raw material extraction and construction waste disposal. And corresponding statistical model, including two computing formulas for single building and a statistical method for regional buildings was designed. Using the proportions of weights from raw materials to building materials and the ratios between raw material weights and destroyed land areas, extended land consumptions at construction stage and demolition stage by per square meter of floor area were calculated as target parameters respectively for three common building structures: brick-concrete, frame and steel structure. Based on building structures, predicted time of demolition and reconstruction, and the target parameters, extended land consumption from all buildings of Shenyang City from 2014 to 2064 in four situations were calculated and compared. The results illustrate that extended land consumption accounts for 1.78% of the whole city area and 29.18% of occupied land, and could be reduced by 80% by improving construction quality for longer serviceable building life and adopting prefabricated construction for greater recycling ratios of scrap building materials. Material flow caused land consumption provides an extended dimension to the concepts on land consumption; the statistical model provides a framework to quantify the relationships between building patterns and land consumption. Our approach permits more accurate land consumption prediction for decision-making in sustainable land utilization.