Although Serbia has introduced a regulation in the 1970’s that requires minimum energy efficiency for new residential and non-residential buildings, and has continuously improved the regulation, the country is taking one further step to make the regulation even much stricter than the previous standard. Under the new regulation, “Regulations on Energy Efficiency in Buildings”, all new buildings will be installed with better thermal insulation of non-transparent elements, including external walls, partitions to unheated space, roofs, ceilings, etc., and with better windows quality, such as five-chamber PVC frames, etc. This allows specific annual heat energy consumption for new residential buildings will decrease from 100 to 60 kWh/m2y, and that for new non-residential buildings from 110 to 70 kWh/m2y and GHGs emission reduction will be achieved