Case study possibilities of reducing energy of residential building

Residential buildings nowadays have a high energy consumption. This is due to the fact, that many of them are still not retrofitted. As the European Union in the new directive (known as the 20-20-20) adopted three major commitments to meet the criteria by 2020, it is necessary to pay attention to the retrofit. The aim of the work is to point out how contribute to reducing energy consumption and why pay more attention to the comprehensive retrofit over the partial retrofit