The thesis presents the role and use of the calculated energetic performance certificate.
Legislation, in which the energetic certification is regulated on this subject, is discussed and
listed. A calculated energetic performance certificate is made for an older building that
consumes a lot of energy. Calculations are made with a computer program KI Energija 2014
in accordance to the valid legislation. Energetic indicators are shown and the values are
compared with the one prescribed by the legislation. Reasons for the high energy
consumption are listed and possible actions for improvements are described. Furthermore,
two main actions (A and B) are described. Action A includes reducing the heat transfer
through the outer building envelope, eliminating thermal bridges and replacing windows and
doors, while action B is very similar to action A, except it has thicker thermal insulation. Both
of them increase the buildings energetic efficiency from class G to class C, based on specific
annual power needed for heating. Nonetheless, with action A we cannot reach values
determined by PURES 2010. On the other hand we can reach them with action B, where the
thermal insulation is thicker and energy consumption is lower.