Thermal Performance of Tall Building Envelope Design in Tropical Urban Region

The construction sector contributes to producing carbon gas emissions of more than 40%, using materials from nature that are quite large, donating waste, and reducing areas for water catchment and green areas. This research focuses on what needs to be considered in the design of energy-efficient buildings is the variable building envelope. Building envelope design is critical in promoting sustainable and energy-efficient tall buildings. Envelope design consists of characteristics and configuration of building materials, that contribute to thermal performance. The performance of a building’s envelope is significant, as it impacts the overall energy consumption of the building. The research aims to verify and investigate the performance of envelopes in tall buildings in the tropical urban region. The research uses a model simulation method that can analytically-quantitatively calculate the energy value of buildings, with a case study at UNS Tower in Surakarta. The UNS Tower building is used as a simulation model to calculate its thermal performance by comparing it with the base case building in the EDGE web application and Overall Thermal Transfer Value (OTTV) calculation. The result shows that thermal performance of UNS Tower does not meet the OTTV standard of 35 W/m 2 according to the Indonesian National Standard (SNI) 6389:2020 for energy conservation in building envelopes. The total OTTV of UNS Tower is 35.17 W/m 2 , with the highest OTTV contribution coming from the parts of the building envelope that utilize unshaded glass materials, specifically the Northwest façade with 47.61 W/m 2 and the Southeast façade with 44.95 W/m 2 . Based on the simulation results using the EDGE web application, the base case shows that UNS Tower is not energy-efficient. The result shows that building envelope selection in the tall building can significantly improve overall energy efficiency. The research offer valuable insights also encourages building envelope design development in tall buildings to improve building energy efficiency.