Visual Req calculation tool for green building evaluation in Taiwan

a r t i c l e i n f o The Ratio of Equivalent Transparency (Req) is a basic index for assessing whether a building is energy-efficient in Taiwan. Req is the ratio of the area of total building envelope and the area of envelope equivalent transparency. Calculation of Req requires not simply the consideration of natural factors such as building location, direction, ambient lighting and sunshine, but also and physical factors such as material, structure, ventilation and sunshade. Current practices in Taiwan of manually calculating Req render the results prone to error, and are also time-consuming. Therefore, this research developed a visual Req calculation tool based on a 3D environment. This system provides users with various visualization tools to view the status and Req results of the building project. Furthermore, object-oriented modeling and parametric design can shorten the time taken to look-up tables and simplify the process of Req calculation, and also help to reduce computation time and errors. In order to cope with projected climate changes brought about by the enhanced greenhouse effect, countries around the world have invested efforts into the development of new energy resources and energy-saving techniques, in addition to the reduction of carbon emission. The concept of a " Green Building " is particularly relevant to these efforts by fully harnessing the available natural resources to reduce pollution, and achieve the aim to create the best environment with the least resources. The greatest opportunities for integrating " green " design strategies occur at the conceptual design stage [1]. The decisions made in the conceptual stage have tremendous impact on building performance in many aspects. For example, by changing design parameters such as shape, orientation, and envelope configuration , a high-quality designed building can consume 40% less energy than a low-quality designed one [2,3]. Therefore, building design must take many different factors into account in order to meet the requirements of a green building. To achieve this purpose, countries worldwide have also started to develop laws to regulate the construction of green buildings. For example, the U.S. Green Building Council (USGBC) is known for the Leadership in Energy & Environmental Design (LEED) [4]. In the UK, the BRE Environmental Assessment Method (BREEAM) has been widely implemented in public building design in order to improve energy efficiency and sustainability of designed buildings [5]. Concurrently in Asia, China's evaluation standard for green buildings is regarded as …