The use of vegetated walls and intensive plantation around buildings has increased in popularity in hot and arid climates, such as those in the United Arab Emirates (UAE). This is due to its contribution towards reducing the heat gain and increasing the occupants' comfort levels in spaces. This paper examines the introduction of plant-shaded walls as passive technique to reduce heat gain in indoor spaces as a strategy to lower cooling demand in hot arid climate of Al-Ain city. Experimental work was carried out to analyze the impact of using plantation for solar control of residential building façades in extreme summer. External and internal wall surface and ambient temperatures were measured for plant-shaded and bare walls. The study concluded that shading effect of the intensive plantation can reduce peak time indoor air temperature by 12 • C and reduce the internal heat gain by 2 kWh daily in the tested space. The economic analysis reveals a payback period of 10 years considering local energy tariff excluding environmental savings.

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To reduce the impact of climate change in the form of low-carbon developments, innovations in sustainable building strategies are imperative. In this regard, the performance of a double-roof house consisting of a photovoltaic panel roof (PV) and green roof (GR) was compared to traditional solar-roof buildings. The synergy between both the PV and GR systems was analysed by numerical simulations and physical modelling across the four seasons. The performance of the systems was assessed on three dimensions: indoor thermal comfort, photovoltaic temperature, and energy yield. The synergy of photovoltaic roofs with green roofs kept the indoor environment 6% more comfortable than solar roofs. The synergy also reduced the photovoltaic temperature by up to 8 °C, extending the PV life span and increasing the energy yield by 18%.

In this study, a novel porous geopolymer mortar (GP) was produced and tested experimentally. Industrial waste materials/by-products were used as constituents of the GP, along with dune sand. One sample was produced as a control sample for benchmarking. For the rest of the samples, 15%, 30%, and 45% by volume, the solid constituents were replaced with expanded polystyrene foam (EPS) beads. These mortar samples were heat cured to depolymerize the EPS to cause porosity inside the samples. Indoor experiments were conducted to evaluate the response of produced porous GP to high heat flux. The porous samples were able to reduce heat transmission across the opposite surfaces. Induced porosity resulted in a decrement in compressive strength from 77.2 MPa for the control sample to 15.8 MPa for 45% porous sample. However, the limit lies within the standards for partitioning walls in buildings and pavements in urban areas to absorb rainwater.

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