Measuring the Sustainability of Construction Projects throughout Their Lifecycle: A Taiwan Lesson

Researchers have proposed many industrial or national sustainability evaluation indicator systems during the past decade, although there has not yet been a project-level sustainability evaluation system for the evaluation and execution monitoring of the sustainability status for a construction project. Without such an evaluation system, it will be difficult for the planners to plan the sustainable project objectives, for the contractors to select the sustainable execution alternatives, and for the facility managers to operate sustainable constructed facilities. To meet the abovementioned requirements, this paper presents an effort conducted in Taiwan to propose a Construction Project Sustainability Assessing System (CPSAS) considering three pillars of sustainability: environmental, social, and economic, based on the theoretical backgrounds from the literature and former successful sustainable projects. The proposed CPSAS comprises four levels: Level 1, 3 main pillars; Level 2, 8 categories; Level 3, 19 sub-categories; and Level 4, 31 indicators. Different selections of indicators for application in different project phases are suggested according to the prioritization via questionnaire surveys. A procedure for sustainable project management with the proposed CPSAS is suggested to the project management team. Finally, three green building projects and two civil infrastructure construction projects of Taiwan were tested to demonstrate the feasibility of the proposed CPSAS. It is concluded that the proposed CPSAS is useful for construction stakeholders to achieve sustainability more effectively during the execution of a construction project.