"According to UNEP, the building sector is estimated to be worth 10% of the global GDP and employs 111 million people. In addition, buildings use about 40% of global energy, 40% of global resources and emit approximately 33% of global GHG emissions. Finally, the fact that people today spend, on average, more than 80% of their time indoors, enhances its social importance. All above indicate the nec ...