used for lighting, heating, ventilation, and air conditioning leads to significant amount of carbon dioxide emissions.
In 2012, the total end-use emission of carbon dioxide from the commercial sector in the United States was 897.9
TgCO2 Eq., which accounts for nearly 18% of the total U.S. carbon dioxide emission [1]. The energy consumption
for commercial buildings is more than 2.3 trillion Btu, and the increasing trend is expected to continue until the
energy produced in the buildings themselves is able to make up for their growing energy needs [2]. To control this
escalating reliance upon fossil fuels and tackle future climate change, it is important to apply effective techniques to
upgrade the existing commercial buildings, developing energy efficient commercial buildings based on the
integration of advanced energy saving concepts and adaptive reuse methods. On one hand, taking Net-Zero Energy
Building (NZEB) concept into commercial retrofits will improve the energy efficiency levels in existing commercial
buildings, exploring the possibilities of involving renewable energy sources in order to reduce their dependence on
external energy infrastructure. On the other hand, since the life of commercial buildings is extended and possible
demolition waste is avoided, net-zero energy commercial retrofits also contribute to the development of a
sustainable urban regeneration form.