This master’s thesis proposes a technical solution for the heating system and the preparation of domestic hot water for the single residence in the area of the city of Križevci. The house consists of four floors (basement, ground floor, first floor, and attic). The heated floors are the ground floor and the first floor with a net area of 178 m2 . The equipment is located in the boiler room in the basement. The heat transfer coefficients of building elements have been selected according to those specified in the national regulation ''Tehnički propis''. The design heat load of the building was determined according to the HRN EN 12831 norm and the average specific heat loss was determined in the amount of 44 W/m2 . The heating system is designed as hot water with forced circulation with an air-to-water heat pump as a heat source in combination with underfloor heating at a temperature regime of 40/35 °C. Pipe loops are dimensioned according to the heat load of a particular room. In the bathrooms, the underfloor heating loops cannot fully cover the heat losses, and pipe radiators are also installed in them. A heating water buffer with a volume of 101 L is installed in the system to ensure a more stable operation of the heat pump. Parallel operation of the heat pump with an electric heater is planned, with a balance point at a temperature of -6 °C is foreseen. The domestic hot water preparation system consists of a bivalent solar tank with a capacity of 372 L, which is primarily heated by solar collectors to a temperature of 45 °C. The solar system is dimensioned in order to fully cover the energy requirements for DHW in the summer period. The rest of the time, when the solar collectors cannot heat the water to the desired temperature, the heat pump takes over the heating of the water. The solar system consists of two serially connected glazing plate collectors directed towards the south at an inclination of 45°. By applying measures in the construction part and installing energy-efficient systems, the house meets low-energy requirements with specific annual required thermal energy 𝑄𝐻,𝑛𝑑 ′′ = 41,63 kWh/(m2 ∙a) and primary energy 𝐸𝑝𝑟𝑖𝑚 = 43,06 kWh/(m2 ∙a). By comparison with the existing situation, significant energy savings in the amount of 90 % as well as a reduction in CO2 emissions in the amount of 67 % were determined. The building sector shows incredible potential for reducing energy consumption and CO2 emissions, which can be seen from the example above.