Acquisition of Shading Coefficient Value for OTTV Calculation on Multiple Glass Buildings by Using Autodesk Ecotect Software

摘要

Various considerations are used in selecting glass as a building envelope material, which is accompanied by the consequence that the glass has the effect of transmitting solar radiation into the building. Where infrared rays that enter into the building cause an increase in room temperature.The amount of solar radiation transmitted through the building envelope is influenced by the ratio of the width of the glass and the total wall area of the building (wall to wall ratio), as well as the type and thickness of the glass used. In commercial buildings, data show that the air conditioningsystem has the largest share up to 65% of total energy consumption. The energy load is caused by internal load and external load. The architectural field contributes to the effort to reduce the burden of energy consumption, especially on the external load with the optimal design of buildingenvelope design. To minimize external loads, SNI 03-6389-2011 determines the design criteria for building envelope with the Overall Thermal Transfer Value (OTTV) value must be less than or equal to 35 Watt/m~(2) . Shading Coefficient is one of the important variables that describesthe amount of solar heat passing through the transparent material in the OTTV calculation process sequence in the building envelope. Shading Coefficient is influenced by the direction of building facade orientation. With valid climatic data, Autodesk Ecotect software can simulate sholar shadevalues of shell plane at a particular orientation and at certain times (especially on dates with extreme climatic conditions in period of the annual tropical climates). This research aims to obtain a more valid and effective shade coefficient value with Autodesk Ecotect software simulationwhich will then be used in the process of calculating the OTTV value of a building. The method used is the observation and data collection on the entire facade of the building then the data will be simulated using software. The expected result is an effective shading coefficient value thatcan be used for OTTV calculations.