Smanjenje potrošnje energenata u građevinama je danas važno pitanje u zgradarstvu. Potreba za smanjenjem potrošnje javlja se prije svega iz ekoloških razloga, a onda i iz ekonomskih razloga. Kako bi se utvrdila potrošnja energije i energetski razred zgrade provodi se energetsko certificiranje zgrada, a potom i energetska obnova postojećih zgrada. Cilj ovog diplomskog rada je ispitati utjecaj zrakopropusnosti zgrade na energetski razred zgrade. Trenutno se prilikom izrade energetskog certifikata ne uzima u obzir stvarna vrijednost zrakopropusnosti jer mjerenja nisu obvezna. Na primjeru stana u Osijeku pri izradi energetskog certifikata napravljena je usporedba utjecaja zrakopropusnosti prema starom i novom proračunu ventilacijskih gubitaka. Nadalje izmjerena vrijednost zrakopropusnosti predmetne zgrade je varirana u nekoliko koraka kako bi se utvrdio njezin utjecaj na rezultate proračuna potrošnje toplinske energije i energetskog razreda zgrade. U tu svrhu u radu je primijenjena metoda analize osjetljivosti. Za mjerenje zrakopropusnosti stana korištena je metoda ''blower-door''.

Reducing energy consumption in buildings recently became an important issue in building construction. The need to reduce energy consumption occurs primarily for environmental reasons and then for economic reasons. In order to determine building energy consumption and energy efficiency rating energy certification is being carried out and afterwards energy renovation of existing buildings as well. The aim of this thesis is to examine an effect of the airtightness of building on building energy consumption. Currently energy certification procedure doesn’t require taking into account real airtightness values. In this thesis an energy certificate was made for apartment in Osijek in order to compare the impact of airtightness values according to old and new calculation procedure of ventilation loses. Furthermore, the measured value of airtightness of the building was varied in several steps in order to determine its impact on the energy consumption. For this purpose sensitivity analysis was applied. Airtightness measurement was carried out by using '’blower-door'’.