Realization and exploitation of buildings involves in European Union about 40% of total energy consumption [1]. One of the elements of rationalization of energy consumption in buildings are the undertakings related with thermal modernization of buildings. The actions related with reducing the energy intensity of buildings are not always correlated with improvement of microclimate conditions in the rooms. Errors in the implementation of the energy efficiency program led to the phenomenon of sick building syndrome. The paper presents the results of the research conducted in a few educational buildings before and after thermal modernization. The research includes energy consumption for the heating of building and selected parameters of the interior microclimate. This analysis was carried out to evaluate the influence of energy saving activities on microclimate interior conditions. It was found that in many cases commonly used gravitational ventilation is not able to ensure the proper conditions of the interior microclimate, and the concentrations of carbon dioxide recorded in the tested rooms exceeded the applicable standards.

The energy-efficient provision of indoor comfort for buildings is one of the most important requirements for modern construction. The greening of buildings is a natural measure to achieve this, for which the most limiting factor is the lack of systematic research on its positive effects. At the Kyiv National University of Construction and Architecture, a series of research on thermotechnical benefits and gas exchange in plant layers has been performed. The cooling effect of plants is up to 4 K. Semi-intensive green roofs on rooms have paths, which absorb solar radiation and load the air-conditioning systems. The proposed solution is to build the paths on the auxiliary premises with low microclimate requirements. The work aims to estimate the heat distribution in green roofs with paths to test the recommendation. Simulation using the Fourier–Kirchhoff equation shows that the path has a trace of higher heat transfer on the ceiling up to an additional 1.8‒2.0 W·m−2. Thus, aligning the paths above the auxiliary premises is recommended, if possible. A better solution is to allow planting of the paths. Using plant-permit pavements and barefoot-in-dew systems such as ZinCo Soft Landscape are examples of such solutions. It is necessary to use grass that can be walked on.

Emission of harmful substances into the atmosphere resulting from the combustion of fuels in the energy production process and road traffic intensity are a key determinants of poor air quality in cities and the creation of an unfriendly environment for people to live in, which has a significant impact on their safety and health. The first step to reducing emissions is to reduce energy consumption. The ecological effect resulting from the thermal modernization of existing residential building stock was estimated. Nature-based solutions were proposed to compensate for the lost green areas in favor of gray infrastructure in the form of green roofs and walls. The possibility of improving environmental conditions by introducing this type of solutions into the urban tissue was assessed. Depending on the type of vegetation, one m ² of green cover is able to absorb an average of 2.3 kg of CO ₂ and 0.2 kg of particulate matter from the air per year. Renewable energy sources are an important element of green buildings. Heat pump may be the most advantageous solution in minimizing emissions combined with low operating costs. Obtaining energy from geothermal sources would be equally beneficial in terms of reducing emissions, but there are risks changes in groundwater levels or soil damage. Solar energy is one of the leading renewable energy sources, especially in hot water installations, where it is possible to reduce energy consumption by up to 50%.

The calculative methods, which are adopted in various fields of engineering, are usually a certain kind of theoretical approximation of reality. The deviations from a full consistency of actual conditions and theoretical assumptions occur also in case of building heating. This work presents the selected results of examinations connected with an annual energy consumption CH and annual final energy demand Qk,H for heating and conducted on the group of educational buildings. The presented analysis and its results regard the group including 46 of 50 educational buildings, which form a municipal group of the buildings of this type. The purpose of presented analysis was to examine the influence of possible occurrence and level of differences between the annual energy consumption CH and annual final energy demand Qk,H for heating of examined buildings. The realization of this purpose is the basis for further research and analysis aimed at determining the dominant reasons of mentioned differences, establishing their level and propose a calculative method for reducing the differences between the values "picturing" the thermal needs of educational buildings in actual (energy consumption CH) and theoretical (final energy demand Qk,H) conditions.

The paper presents the results of the research in building after thermal modernization. The analysis includes energy consumption for heating of the building, the nature of the microclimate in rooms and pollutant emissions to atmosphere of fuel combustion products. This analysis was carried out to evaluate the influence of energy saving activities on microclimate interior conditions and the state of the external environment.