Nowadays, the growth and the development of communities have a large impact on the natural environment. Construction field is one of the largest sources of greenhouse gas emissions and energy consumption around the globe. To emphasize the importance of green building and to estimate the environmental impact of buildings, a variety of Green building rating systems have been created and developed all over the world. Among them, LEED standard of United States is one of the most common Green building rating systems used globally. However, it is difficult to apply LEED standard because the requirement in the rating system is extreme complex. Thus, it raises difficulty for engineers, especially Taiwanese engineers - because Green building standard in Taiwan, namely EEWH standard, is easy to be applied with simple procedures. This research combines the easy calculation way of EEWH and the code analysis of LEED to create an approximate energy efficiency function for LEED. The range of application is office building in Taiwan and Vietnam. Utilizing that approximate function, engineers are able to estimate the building energy efficiency based on LEED standard quickly and simply. This study also puts forward a proximate model which estimates the effect of natural ventilation on building energy - enabling engineers to have an overall view of building energy – and to facilitate the satisfaction of the LEED requirement.

Nowadays, the growth and the development of communities have a large impact on the natural environment. Construction field is one of the largest sources of greenhouse gas emissions and energy consumption around the globe. To emphasize the importance of green building and to estimate the environmental impact of buildings, a variety of Green building rating systems have been created and developed all over the world. Among them, LEED standard of United States is one of the most common Green building rating systems used globally. However, it is difficult to apply LEED standard because the requirement in the rating system is extreme complex. Thus, it raises difficulty for engineers, especially Taiwanese engineers - because Green building standard in Taiwan, namely EEWH standard, is easy to be applied with simple procedures. This research combines the easy calculation way of EEWH and the code analysis of LEED to create an approximate energy efficiency function for LEED. The range of application is office building in Taiwan and Vietnam. Utilizing that approximate function, engineers are able to estimate the building energy efficiency based on LEED standard quickly and simply. This study also puts forward a proximate model which estimates the effect of natural ventilation on building energy - enabling engineers to have an overall view of building energy – and to facilitate the satisfaction of the LEED requirement.

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