Evaluating the impact of tree planting patterns on outdoor thermal comfort and microclimate: a case study of open spaces among high-rise buildings

Samadpour Shahrak, Mahsa

doi:10.22034/aes.2026.529003.1106

Evaluating the impact of tree planting patterns on outdoor thermal comfort and microclimate: a case study of open spaces among high-rise buildings

Document Type : Original research article

Author

Mahsa Samadpour Shahrak

Department of Architecture and Urban Planning, Technical and Vocational University (TVU), Tehran, Iran

10.22034/aes.2026.529003.1106

Abstract

Vegetation plays a significant role in enhancing thermal comfort and regulating outdoor temperatures. This study aimed to find a suitable pattern of tree arrangement to improve the climatic conditions of the surrounding environment and comfort conditions. Assuming that changing the pattern of the tree arrangement is effective in microclimate conditions and thermal comfort. For this purpose, four different types of planting patterns, including tree arrangements in the four-row pattern (Quadruple pattern), six-row pattern (Sextuple pattern), row pattern, scattered pattern, and treeless conditions, have been studied. To achieve this purpose, ENVI-met (5.6.1) was used to simulate and measure T_a (Air temperature), and T_mrt(Mean Radiant Temperature), and also Rayman software (1.2) was used to measure PET (Physiological Equivalent Temperature). The data extracted from the software is validated by comparing it with local data. This research has been done in the open space around high-rise residential buildings in Tabriz, Iran. The results indicate that changing the planting pattern can have some effects on improving the surrounding environmental conditions. Both row and scattered patterns have a better impact on environmental comfort conditions, and the scattered pattern has a better result on the micro-climatic conditions of the region. As a result, considering both factors (Thermal comfort & Microclimate), the scattered pattern is the best scenario compared to other scenarios.

Highlights

· Planting trees improves the comfort conditions in the surrounding environment.

· PET, were simulated using ENVI-met and Rayman in the Tabriz case study.

· Four tree patterns (Quadruple, Sextuple, Row, Scattered) were evaluated in open spaces to optimize microclimate conditions.

· The Scattered pattern is the optimal strategy for balancing microclimate conditions and thermal comfort.

Keywords

ENVI-met

Microclimate

Open space

Planting pattern

Rayman

Thermal comfort

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