1. Žana Stevanović, University of Belgrade, Vinča Institute of Nuclear Sciences, Serbia, Serbia
2. Ivan Lazović, University of Belgrade, Vinča Institute of Nuclear Sciences, Serbia, Serbia
3. Mladen Tomic, Serbia
4. Predrag Živković, Faculty of Mechanical Engineering Niš , Serbia
To provide better insulation of a building it is necessary to achieve equilibrium of three types of relative humidity: indoor humidity, humidity in walls and outdoor humidity. Equilibrium relative humidity is a form of steady state heat and mass transport through building insulation system. However, it is difficult to achieve equilibrium relative humidity because outdoor relative humidity is constantly changing and because of transient behavior of buildings. So this transient outdoor relative humidity has an influence on the relative humidity in walls, indoor humidity and heat transport through walls. High relative humidity can cause surface condensation. The paper analyzes how climate change (outdoor relative humidity and dew point temperature) influence on surface condensation. There were made a comparison between climate conditions in Belgrade based on TMY3 and meteorological year April 2015 - April 2016. As a result, there was obtained the difference in sorption/desorption isotherm of typical building materials that are installed in Belgrade residential area.