A quality family house with low operating costs, built to a passive standard providing healthy housing, will be a matter of course in the coming years. Passive wooden construction comes to the forefront of the construction of a family house for maximum use of solar radiation and heat gained through glazed structural surfaces or from internal heat gains. The diploma thesis focuses on the calculation of heating demand in passive wooden buildings. The work compares different types of insulating glazing in combination with three window frames. Among all combinations, the heat transfer coefficient of the entire window is determined and how the combination of the frame and glazing used affects the heat demand for heating. Based on the obtained calculations, this work determines the best possible combination of glazing with a frame, and the influence of the selected window on overall heating demand of the building. This diploma thesis points out the importance of correct window construction for the heating needs of the passive house.