Development of decision-making tool for construction method selection: choosing and optimizing offsite construction

Offsite construction is considered as a possible solution for addressing time, quality and cost concerns associated with traditional construction method. Successful implementation of these methods on a particular project requires systematic analysis and early decision making based on specific factors of the project. There is a lack of an efficient systematic approach that can match the changing needs, deal with the growing complexity of building projects and take into consideration recently developed innovations, technologies and regulations. The objective of this study is the development of an early-phase decision tool to support construction project teams in selecting construction methods. This paper proposes a multi-level decision framework. The first level conducts a feasibility study and evaluates the applicability of offsite construction. The second level proposes an integrated approach for the decision-making problem that combines the Analytical Hierarchy Process (AHP) and the Preference Ranking Organization Method for Enrichment Evaluations (PROMETHEE). The combination of both approaches enables a careful evaluation of different construction methods and scenarios for the same project. A computerized tool is developed and tested on a case study to help a project team in the decision-making process.