Optimal multi-use cycle scenarios for temporary demountable modular building systems: An environmental sustainability perspective

Currently, there is limited understanding of how many years and how many times building systems can be reused while remaining minimal adverse environmental impacts from a multi-use cycle perspective. This study aims to identify optimal multi-use cycle scenarios for a demountable modular unit that achieves minimal environmental impacts. Multi-objective optimization was conducted to determine the optimal number of use cycles and the duration of each cycle, focusing on minimizing both environmental cost and residual value. Six Pareto-optimal scenarios were identified to minimize both the environmental costs of embodied and operational carbon emissions and residual value. They are [5-yr, 5-yr], [5-yr, 25-yr], [10-yr, 25-yr], [15-yr, 25-yr], [20-yr, 25-yr], and [25-yr, 25-yr], implying that the optimal number of use cycles is two. The finding serves as valuable insight for developing end-of-life planning strategies that promote the sustainable reuse of demountable modular building systems. • Identify optimal reuse scenarios by examining environmental cost and residual value. • The optimal number of use cycles for the investigated modular building system is two. • The length of the first use cycle should not be longer than the second one.