Evaluating Carbon Payback Period in Parametric Facade Optimization Using Genetic Algorithms and Multi-Criteria Decision-Making
Journal
Proceedings of the International Symposium on Automation and Robotics in Construction
Start Page
1880
End Page
1887
ISSN
2413-5844
ISBN (of the container)
978-064583223-5
ISBN
[9780645832235]
Date Issued
2026-06-22
Author(s)
Abstract
Facade shading systems can reduce cooling energy demand in office buildings located in tropical-humid climates, but the additional materials required may also increase embodied carbon emissions. Although many parametric facade optimization studies focus on operational energy and daylight performance, the temporal relationship between embodied carbon and operational carbon savings remains insufficiently explored. Carbon Payback Period (CPP) is therefore rarely integrated into parametric facade optimization and decision-making workflows. This study proposes an integrated framework combining Life Cycle Assessment (LCA), CPP, multi-objective optimization, and Multi-Criteria Decision-Making (MCDM) to support low-carbon facade design. A parametric facade model was developed for a medium office building in Taipei, Taiwan, with variations in window-to-wall ratio, glazing type, shading depth, and window configuration. Energy and daylight performance were simulated using Honeybee and Ladybug, while Wallacei was used to optimize Energy Use Intensity (EUI), Annual Sunlight Exposure (ASE), Whole-Life Carbon (WLC), Carbon Payback Period (CPP), and Spatial Daylight Autonomy (sDA). The resulting 20 Pareto-optimal alternatives were then evaluated using TOPSIS under multiple weighting scenarios. The results revealed clear trade-offs between operational efficiency and life-cycle carbon performance. Building Type 02 emerged as the most robust and balanced alternative, ranking first across the energy-priority, carbon-priority, and balanced scenarios and achieving a positive CPP of 8.95 years. These findings highlight the value of CPP as a complementary time-based indicator for verifying whether additional embodied carbon can be offset by future operational carbon savings in facade design decision-making.
Event(s)
43rd International Symposium on Automation and Robotics in Construction, ISARC 2026,22 June 2026 - 26 June 2026,Singapore
Subjects
Carbon payback period
Genetic algorithms
Life cycle assessment
Multi-criteria decision-making
Parametric facade design
Tropical-humid climate
Publisher
International Association for Automation and Robotics in Construction (IAARC)
Type
conference paper