The thesis discusses the impact of thermal bridges on consumption of heating energy in a single-family detached house. The thermal bridges were identified with an IR camera. Based on identified thermal bridges calculations were carried out with programs TEDI and TOST in accordance with the methodology specified in the applicable legal basis. The significance of thermal bridges was shown with a comparison of calculations made with and without acknowledging the thermal bridges. Results have shown that thermal bridges can have an impact of 15,4 % to 17,4% on the energy consumption in the present building. The thesis demonstrates the importance of connecting IR photos and calculations and presents practical options of using this method.