Optimizing Building Volume and Solar Access in Isfahan's Urban Texture: A Solar Envelope Approach Using Parametric Design Tools

Najafi, Ahmad; Goodarzi, Ali; Mortaheb, Ramtin

doi:10.22034/ijumes.2025.2049602.1285

Optimizing Building Volume and Solar Access in Isfahan's Urban Texture: A Solar Envelope Approach Using Parametric Design Tools

Document Type : Original Article

Authors

Ahmad Najafi ¹

Ali Goodarzi ²

Ramtin Mortaheb ³

¹ Department of Urban Planning, Isf.C., Islamic Azad University, Isfahan, Iran.

² Department of Architecture, Science and Research Branch, Islamic Azad University, Tehran, Iran

³ Department of Architecture and Urban Planning, Faculty of Engineering and Technology, Shahid Ashrafi Esfahani University, Isfahan, Iran

10.22034/ijumes.2025.2049602.1285

Abstract

This study investigates the application of Solar Envelope methodology integrated with Parametric Design tools to optimize building volume and Direct Solar Access in Isfahan’s urban context. Through comprehensive Environmental Simulation using Rhino/Grasshopper and Ladybug plugins, this research develops an innovative approach to Urban Planning that balances construction density with solar rights. The Energy Optimization analysis demonstrates that the Solar Envelope method achieves a 26.13% increase in buildable volume and 41.11% increase in area compared to current regulations, while enhancing solar energy on adjacent building facades by 2.60%. The study employs Parametric Design workflows to generate and evaluate multiple solardriven alternatives, ensuring Direct Solar Access during critical periods (December 21st, 8 am-4 pm). Comparative analysis Isfahan, Mashhad, and Tabriz validates the climateresponsive nature of the Solar Envelope approach. Results indicate that current Urban Planning regulations inadequately address solar access rights, often leading to violations. The proposed Environmental Simulation methodology offers a robust framework for Energy Optimization in dense urban developments, demonstrating that 100% land occupancy can be achieved while maintaining solar access standards. This research provides critical evidence for updating architectural and Urban Planning laws in Iran to incorporate Solar Envelope principles for sustainable urban development.

Graphical Abstract

Optimizing Building Volume and Solar Access in Isfahans Urban Texture: A Solar Envelope Approach Using Parametric Design Tools

Highlights

The solar envelope approach facilitates a significant 26.13% increase in buildable volume compared to current regulations, while simultaneously enhancing solar energy access on the facades of adjacent buildings by 2.60%.
The findings reveal a critical deficiency in contemporary urban planning regulations regarding the balance between construction density and solar rights, a challenge for which the proposed parametric methodology offers a viable solution.
The proposed methodology strategically optimizes solar access by substantially increasing the solar energy received by adjacent building facades, despite a marginal 1.22% reduction in direct sunlight hours on the surrounding ground surface.

Keywords

Direct Solar Access

energy optimization

environmental simulation

parametric design

solar envelope

urban planning

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