Near-zero energy building (NZEB) means a building with very high energy efficiency, determined according to the methodology for calculating the energy performance of a building and whose near-zero or very low energy demand is covered to a very large extent by energy from renewable sources, including energy produced on site or in the vicinity of the building.
The requirements and technical characteristics of a building with near-zero energy consumption were defined in a Decree issued by the Minister of Energy, Trade and Industry in 2014. These requirements became mandatory for new buildings with the current minimum energy performance requirements issued in 2020.
In addition, the requirements for CSMEs can be used by those wishing to renovate and upgrade an existing building to a very high level of energy efficiency.