Evaluation of effective strategies to reduce the heat island in urban centers with emphasis on cold surfaces and green surfaces (Case study: Redesign of an urban block in the Raah-Aahan, Tehran)
Subject Areas : Architecture and urbanism
Golnoush Parsi
1
,
Hossein medi
2
,
Maryam Azmoodeh
3
1 - Master Student of Architecture and Energy, Imam Khomeini International University, Qazvin, Iran.
2 - Faculty member, Imam Khomeini International University, Qazvin, Iran.
3 - Faculty member, Imam Khomeini International University, Qazvin, Iran. *(Corresponding Author)
Keywords: Heat- island, Heat- island mitigation strategies, Tehran Raah-Ahan neighborhood, Envi-met simulation.,
Abstract :
Background and Objectives: thermal comfort is one of the requirements in the cities. However, lots of cities have thermal problems recently which has been caused due to heat islands. Tehran has also faced urban heat island in some urban centers. The main goal of this research is redesigning and introducing a model for the built environment such as roads, façade and roof materials and finding a synthesis of effective strategies to eliminate heat island in Tehran Raah-Ahan neighborhood.
Material and Methodology: This study has been done in February,2021. The method of this research is experimental based on an urban case study. Data collection has been done by direct and indirect observations and analysis has been done by Envi-met software. First, current situation was analyzed based on some environmental parameters and then each mitigation scenarios, based on the same parameters, has been analyzed.
Findings: roads material have a great effect on increasing the temperature and changing them with reflective materials reduces temperature meaningfully. The combination of reflective and green roof is also effective although green roof is a better alternative due to further lowering the temperature and increasing evaporative humidity. The priority of adding green wall to the facades is south, west, north and east direction. In addition, implementing green wall without other strategies has little effect on reducing temperature.
Discussion and conclusion: Implementing reflective roof, green roof and green wall together is a proper model for mitigating heat island effect in railway station neighborhood or any similar neighborhoods.
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