## 1 Introduction  
Heat is one of the main factors influencing the comfort of living or staying in the premises of residential buildings as well as public utility. It affects not only our well-being, efficiency and effectiveness but also the financial aspect related to the need to rationalize the costs of property maintenance in the phase of its exploitation and the impact on environmental protection by reducing carbon dioxide emissions to the atmosphere [1]. Single- and multi-family houses but also public buildings account on average for about 41% of total energy consumption in the European Union. These estimates reinforce the thesis that the need to reduce energy consumption in buildings, especially for heating and air conditioning, is of great importance for rational energy management. According to the report of the European Environment Agency in the European Union, energy used for space heating represents 68% of global energy consumption in buildings [2]. In Poland it is 71% [3]. For the needs of hot water, 13% is used, for lighting and other electrical appliances - 14% and only 5% for preparing meals [2]. Potential savings resulting from thermal upgrading of buildings are estimated at the level [3]:  
* 33-60% to reduce energy consumption by improving thermal insulation of walls,
* 16-21% for the modernization of the ventilation system,
* 14-20% to improve the thermal insulation of the window joinery,
* 10-12% for regular inspections and modernization of central heating boilers. The above-mentioned activities, in order to achieve the assumed effect, must take into account the so-called human factor, namely, additionally the behavior, attitudes and habits of residents- users of buildings- must change. Changing their attitude towards energy-saving measures, such as, for example: room temperature control (by means of thermostatic valves) depending on needs, limiting excessive ventilation of rooms and others, can bring real savings of 5% to 15% [4]. In recent years, a huge progress has been observed in technological solutions used in residential and commercial buildings. Starting from architectural solutions up to heating technology. More and more complicated technical innovations are being applied nowadays, whose task is to improve the living comfort in buildings. Intelligent buildings, with the help of innovative systems, have become not only more comfortable but also safer. The rapidly developing technologies make it possible to apply these modern solutions in buildings where people stay every day. Optimization of energy consumption and related energy efficiency are increasingly often analyzed in depth in practically all aspects of life of modern society. These issues, in a special way, also affect buildings and their infrastructure, because they are one of the most energy-intensive areas of human functioning. Users of residential units but also of public buildings, attach increasing importance to the possibility of offering high comfort in them and also want to make widespread use of the achievements of modern heating, ventilation or multimedia technology. The research conducted on the quality of the internal environment shows that users of various types of buildings--including thermally improved buildings--feel satisfied with their living conditions, which has a positive effect on health and productivity and at the same time translates into ecological attitudes [5; 6; 7; 8]. This situation determines the need for a new approach to the very design phase of the planned facilities and in the case of existing buildings, their modernization and adaptation to contemporary trends and requirements [9]. These actions are taken not only in the scope of improving the comfort of use but also energy efficiency and, what is important, safety. Therefore, it has become necessary to conduct research in the scope of already available and search for new, functional building automation systems. All this in order to continuously optimize the consumption of electricity, heat and other media in buildings [10].