Revisiting building height restriction policy in the historic center of Seoul: Exploring performance-based height management using view shadow simulation

This study empirically explores 3D isovists to explore an alternative approach to a 90 m height cap in Seoul’s historic center. We introduced the concept of “view shadow” in the city center to explore potential room for growth: (1) areas hidden by existing buildings and (2) areas visible but not altering the current skyline. The proposed approach integrates the concept of view shadow cast by existing towers to minimize visual impact and preserve iconic and historic views. The simulation findings indicate that a significant portion, approximately 31 sites or 58.5% of the total, can accommodate taller towers than 90 m without compromising the integrity of the historic skyline. The study demonstrates the ability to increase the floor area by 74% and up to 137% from existing conditions to revitalize Seoul’s historic center.