Posljednjih nekoliko desetljeća klima se na našem planetu mijenja i sve se više razvija svijest o posljedicama klimatskih promjena koje su uzrokovane povećanom koncentracijom stakleničkih plinova u atmosferi. Prioritet u području energetike i gradnje postaju energetska učinkovitost u zgradama, održiva gradnja te primjena obnovljivih izvora energije jer je sektor zgradarstva najveći pojedinačni potrošač energije. Energetska obnova postojećih zgrada i gradnja novih energetski učinkovitih zgrada vodeća je tema u području graditeljstva, zaštite okoliša i održivog razvoja zbog mogućnosti velikih ušteda energije u tom sektoru. Veliku količinu energije moguće je uštedjeti promjenom ponašanja korisnika zgrade. Odabir mjera za poboljšanje energetske učinkovitosti ovisi o energetskom stanju i vrsti zgrade, o načinu njenog korištenja te o lokaciji zgrade. Primjenom mjera postižu se značajne uštede energije, smanjuju se troškovi korisnika zgrade te emisija stakleničkih plinova, čuva se okoliš, povećava se trajnost zgrade, postiže se ugodniji boravak u zgradi, povećava se kvaliteta života i čuva se zdravlje ljudi. Predmet diplomskog rada je višestambena jednokatnica iz 1957. godine za koju su na temelju analize i proračuna postojećeg stanja predložene mjere za poboljšanje energetske učinkovitosti. Proveden je proračun nakon primijenjenih mjera te su uspoređeni rezultati proračuna postojećeg i projektiranog stanja. Pri proračunima su poštivane odredbe Pravilnika o energetskom pregledu zgrade i energetskom certificiranju (Narodne novine broj 48/14., 150/14., 133/15., 22/16., 49/16., 87/16., 17/17.) te Tehničkog propisa o racionalnoj uporabi energije i toplinskoj zaštiti u zgradama (Narodne novine broj 128/15.).

Over the last few decades the climate on our planet has changed and the awareness of the consequences of climate changes caused by increased concentration of greenhouse gases in the atmosphere is becoming more developed. Priority in the field of energy and construction becomes energy efficiency in buildings, sustainable construction and application of renewable energy sources because the building sector is the largest individual energy consumer. The energy refurbishment of existing buildings and the construction of new energy-efficient buildings is the main topic in the field of construction, environmental protection and sustainable development due to the possibility of large energy savings in this sector. A large amount of energy can be saved by changing the behavior of the building user. The selection of measures to improve energy efficiency depends on the energy status and type of building, the way the building is used and the location of the building. Significant energy savings are achieved by implementing measures to improve energy efficiency. Also, the operation and greenhouse gases emissions are reduced, the environment is protected, the durability of the building increases, a more comfortable indoor climate in the building is achieved, the quality of life is increased and the health of the people is preserved. The subject of this graduate work is the one-story apartment building built in 1957. Measures to improve energy efficiency have been suggested on the basis of analysis and calculating of the current building state. The evaluation was also made after the implementation of the each measure. The work compares the results of the evaluation of the existing building energy performance and the situation after the implementation of the measures. This evaluation of building energy performance was done in respect to the Ordinance on energy audits and energy certification of buildings ( Official Gazette 48/14, 150/14, 133/15, 22/16, 49/16, 87/16, 17/17) and the Tehnical regulation on energy economy and heat retention in buildings (Official Gazette 128/15).