Multi-objective optimization of an industrialized wall system for sustainable housing

The construction sector is a major contributor to global energy consumption and greenhouse gas emissions, making it a central focus of sustainable development. Concurrently, the housing deficit has driven the adoption of industrialized construction systems in residential projects. This study presents a multi-objective optimization of a modular wall system that integrates sustainability principles and alternative insulation materials to reduce energy demand for heating and cooling, carbon footprint, construction costs, and construction time. A workflow was developed, starting with the definition of a case study, including its location and architectural configuration for a cold climate, followed by dynamic energy simulations and optimization using evolutionary algorithms. A total of 157 simulations were conducted with DesignBuilder and EnergyPlus, assessing combinations of insulation materials (sawdust, wheat straw, and glass wool) and panel thicknesses. The optimal configuration included plywood panels and wheat straw insulation. Compared to a traditional wall, this solution achieved an 11.12% reduction in energy demand, a 1.80% reduction in carbon footprint, and a 1.80% reduction in cost, along with a construction speed up to eight times faster under controlled test conditions. Additionally, when considering a more realistic heat pump scenario (CoP = 3), the operational carbon footprint decreases by approximately 66%, reinforcing the environmental potential of the proposed system. These results demonstrate the capacity of optimized industrialized systems to deliver energy-efficient, low-impact, and scalable housing solutions, particularly in cold climates with urgent social housing needs. • Optimized wall system cuts energy demand by 11.1% in cold-climate housing • Industrialized modular design lowers carbon footprint and cost by 1.8% • Assembly time is up to 8× faster under controlled test conditions • Multi-objective method defines optimal insulation type and thickness • Wheat straw insulation offers best thermal and environmental results