THE DESIGN, DEVELOPMENT, AND IMPLEMENTATION OF SMART GREEN ROOFS (SGR) IN HOT ARID CLIMATES - CASE OF DOHA, QATAR

Abstract

Greening the city is an old-conventional approach that has been rediscovered in the roof system to improve the urban environment in a smart and sustainable manner. Despite the growing literature on green roofs, there remains a lack of studies exploring the implementation of smart digital applications. Moreover, there is an absence of research addressing the utilization of smart green roofs (SGRs) in hot arid regions, making it challenging to evaluate their suitability as a heat mitigation strategy for Qatar. The SGR incorporates smart sensors linked to Internet of Things to automate optimal irrigation performance. The research aims to design, develop, and implement SGRs optimal for the hot arid climate of Qatar. It seeks to evaluate the influence of SGRs on the users' thermal comfort and building's energy consumption, employing qualitative and quantitative tools. Employing questionnaire and interview approaches to gather users' perceptions. Real-time experiment and DesignBuilder simulations are utilized to compare an SGR against a non-green roof (bare) on an office building in Doha, Qatar. Real-time data measured plant performance, wind speed, temperature, humidity, and heat flux. Whilst simulation data extracted wind speed, temperature, humidity, heat flux, energy consumption, thermal conductivity, U-Value, and R-Value. Statistical analysis, p value tool, is employed to establish the significance and relationship between environmental factors and plant performance, including color, height, and leaf area index (LAI). Performance of SGRs, associated with an increase in LAI and plant height, Performance of SGRs, associated with an increase in LAI and plant height, effectively reduced indoor temperatures, heat flux, and relative temperature. SGR's thermal performance improves with an increase in LAI, plant height, and soil moisture, reducing the U-Value and amplifying the R-Value. The resulting improved insulation directly influences a diminished amount of energy consumption. These effects enhance the users' thermal comfort concerning the indoor environment quality. Urban planners, architects, and engineers can further implement the integration of the SGR as a valid green technology due to its lightweight element and low maintenance requirements. Finally, this study aims to design, develop, and implement SGRs and formulate design recommendations that can be applied on existing and new roofs in Qatar.