Effect of glass type variation on overall thermal transfer value (OTTV) and HVAC energy consumption: a case study of the Bank Syariah Indonesia building

Abstract

The building envelope, particularly the glazing on the façade, is one of the main pathways for solar heat gain into a building, which can increase the Overall Thermal Transfer Value (OTTV), cooling load, and HVAC energy consumption. This study aims to analyze the effect of glass type variation on OTTV values and cooling system energy consumption in the Bank Syariah Indonesia building. The study employs a quantitative method through simulation-based calculations in accordance with SNI 6389:2020. The glass variations analyzed include clear glass as the existing condition, tinted glass, and coated glass. Research data were obtained through field observation, interviews with building management, and documentation studies. The results show that the OTTV value under the existing condition is 27.47 W/m². The use of tinted glass reduces the OTTV value to 25.40 W/m², while coated glass yields the lowest OTTV value of 25.10 W/m². This reduction in OTTV value leads to a decrease in cooling load and cooling system energy consumption compared to the existing condition. Based on the analysis results, coated glass is the most effective alternative, as it produces the lowest OTTV value and offers greater energy-saving potential for office buildings.