Executive Summary : | Objective: The building sector is one of the foremost consumers of energy. The energy efficient building requires passive design measures for a living. In the thermal performance of any building, one of the dominant and decisive elements is its envelope. The building envelope takes care of energy requirements and thermal comfort of building. The most of the residential buildings in India are single or double storied, the heat transmission across the building roof is about 50-70% of the total heat entry for the rooms below the exposed roof (sunlight roof). Hence, considerable efforts are required to reduce the heat transmission across the roofs. Researchers across the globe have tried different cool roof systems and found that, cool roof systems can offer certain amount of energy efficient performance, and also occupant comfort. However, there is no universal design guidelines available on this.,This study, focuses on development of Innovative cool roof with improved thermal & energy performance along with real time monitoring of roof surface temperature and indoor room air temperature by the application of cool roof on a demo building. Summary: Roof can bring lot of heat into buildings during summer especially when there is high amount of solar radiation. A roof that decreases heat ingress into the buildings by reflecting and emitting the sun ‘s heat back into the sky is said to be a cool roof. Solar reflectivity (SR) and infrared emissivity (IE) are two main properties of the roof surface which determine the performance of the cool roof. Roofs with high-reflectance (solar reflectance) coating, commonly known as cool roofs, can stay cool in the sun, thereby reducing building energy consumption. India being a country with hot tropical climate, in most of its states there exist a yearlong cooling requirement, and hence cool roof promises to be a worthy technology in decreasing the cooling energy consumption. The predicted average global air temperature rise of 2°C represents a critical limit by 2030 and existing buildings are widely reported to operate inefficiently, the optimization of buildings’ performance is a key issue to reduce global energy demand (IEA, 2009). Traditionally, buildings are constructed with locally available materials like stone, wood, mud and lime. At present various cool roof technologies are available which specify the thermal performance based on simulation studies. This study, focuses on development of Innovative cool roof with improved thermal & energy performance along with real time monitoring of roof surface temperature and indoor room air temperature by the application of cool roof on a demo building. |
