Constructability obstacles: an FCM-based dynamic modelling

Construction projects often suffer cost/time overruns and reduced quality due to design-construction mismatches and lack of constructability. This dynamic process involves evolving variables requiring quantified, non-binary assessment to optimise buildability. This study identifies key obstacles to constructability implementation and models their interdependencies and impacts on project time, cost, and quality using fuzzy cognitive mapping (FCM). Based on literature, expert input, and an Iranian megaproject case study, a three-layer FCM with 28 obstacles, 10 consequences, and 3 failure modes was developed. Scenario analysis revealed critical barriers: viewing constructability as a cost rather than investment, contractors’ unwillingness to engage in design, inflexible contracts, and limited contractor knowledge. Results enable targeted planning, early integration, and cultural shifts to reduce duplications, enhance effectiveness, and support constructability from initial design phases.