The main goal in the design, construction and operation of buildings should be to create a favourable environment for people. Properly selected material, construction and installation solutions allow for the creation of healthy buildings, while significantly reducing energy consumption and costs. Impact on health and methods to reduce exposure to indoor air pollution vary depending on the type of building and its intended use. The improvements should concern, first of all, proper formation of indoor air quality and the mitigation of existing exposures in the building and its surroundings. The paper discusses the phenomenon of sick building syndrome and the impact of improper ventilation and poor air quality in rooms on the formation of the syndrome symptoms. The results of research on the condition of the interior environment of pre-school, school and indoor apartments located in a multi-family residential buildings are presented. The results of measurements of selected thermal parameters of the interior microclimate, i.e. air temperature and relative humidity as well as carbon dioxide concentration, are presented. Based on the conducted questionnaires the phenomenon of the sick building syndrome was assessed among room users. Carbon dioxide levels above 1000 ppm have been exceeded, especially in educational buildings. The respondents mainly complained about the deteriorating air quality with the passage of time indoors, irritation of the eyes and respiratory tract, as well as fatigue and headache.