Iranian Sustainable Building Scientific Association International Journal of Urban Management and Energy Sustainability 2538-1628 6 4 2025 10 01 Optimizing Building Volume and Solar Access in Isfahan's Urban Texture: A Solar Envelope Approach Using Parametric Design Tools 49 62 731559 10.22034/ijumes.2025.2049602.1285 EN Ahmad Najafi Department of Urban Planning, Isf.C., Islamic Azad University, Isfahan, Iran. 0000-0003-4005-636X Ali Goodarzi Department of Architecture, Science and Research Branch, Islamic Azad University, Tehran, Iran 0000-0002-0370-9053 Ramtin Mortaheb Department of Architecture and Urban Planning, Faculty of Engineering and Technology, Shahid Ashrafi Esfahani University, Isfahan, Iran 0000-0002-6909-4741 Journal Article 2025 01 01 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. https://www.ijumes.com/article_731559_f923cb3121620ee12d08395c0e64dbb7.pdf