Various methods can be used to reduce energy consumption in buildings. One of them is the tightening of energy requirements, which, like other methods, cannot result in a worsening of the indoor environmental quality. The article presents a study on the impact of changes in the thermal insulation of the building envelope on the energy demand, heating costs, and emissions. Mathematical models of the dependence of the index of annual usable energy demand for heating (EU_H) of a residential house on the thermal transmittance coefficients (U_i) of selected building elements were developed. Values of U_i were adopted at three levels, corresponding to the maximum required values—as approved in Polish law for the periods from 2014, 2017, and 2021. The analyses were conducted for the location of the building in three of the five climate zones of Poland. It turned out that the differences in the energy demand in various locations in Poland amount to 32.6%. The change in U_i in the analyzed period causes a decrease of EU_H by almost 27%. Financial savings and a reduction of emissions strongly depend on the fuel used in the building. Increasing the level of thermal insulation of walls increases the perceptible temperature in rooms by 1.2–1.5%.

This paper presents a case study on how to improve the energy efficiency of an institutional building of significant heritage value through retrofitting the external wall system. This building is located in Upper Silesia, Poland. Due to the architectural value of the facade, thermal insulation had to be applied from the inside. As part of this publication, basing on the measurements and simulations, the authors present the results involving the improvement of energy efficiency of the insulated wall. On this basis, they also demonstrate the impact of insulation from the inside on the change of humidity inside the room. The tests were carried out both quantitatively by means of heat flux measurement and qualitatively by means of infrared temperature measurement. The research was supported by numerical modeling. The obtained results indicate that the thermal insulation used in the form of mineral insulation boards applied from the inside improves thermal insulation of the wall. Thus, heat losses through the examined envelope were limited. Computer simulations indicated that no condensation may occur under the condition considered.

The article is focused on the airflow in a ventilation system in a building. The work examines the methods which enhance the chimney effect. In this paper, three cases with different chimneys were analyzed for the full-scale experiment. These cases were characterized by different geometrical and material parameters, leading to differences in the intensity of the ventilation airflow. The common denominator of the cases was the room with the air inlet and outlet to the ventilation system. The differences between the experimental cases concerned the chimney canal itself, and more precisely its part protruding above the roof slope. The first experimental case concerned a ventilation canal made in a traditional way, from solid ceramic brick. The second experimental case concerned the part that led out above the roof slope with a transparent barrier, called a solar chimney. In the third experimental case, a rotary type of chimney cap was installed on the chimney to improve the efficiency of stack ventilation. All these cases were used to determine the performance of natural ventilation—Air Change per Hour (CH). Additionally, the paper presents a technical and economic comparison of the solutions used.

The interior microclimate is a collection of all physical and chemical parameters of rooms affecting the human body, objects and a building. The values of these parameters are directly influenced by the type of installations in the building, such as heating, ventilation and lighting. While...

The article introduces material and technological characteristics in insulation of external partitions from the inside. Selected joints of external partition walls were analyzed: corner joint of external walls and wall-window joint in a frame cross-section. The numerical calculations were performed using TRISCO and WUFI software with various isolation thickness and location. Basic physical parameters were defined: linear heat penetration coefficient Ψ, temperature distribution, temperature factor f_Rsi and real pressure distribution of steam and saturated steam, and humidity increase of external walls and their joints for insulation applied from the inside. Based on calculations and analyzes performed design recommendation were formulated resulting from application of insulation from the inside, arising from binding requirements for heat and humidity.

Designing, constructing and using of buildings with low energy consumption are a complex process requiring knowledge of architectural design, construction physics and building systems with the use of renewable energy sources (RES). The article presents the legal bases and characteristics of low-energy buildings. Implementation of the binding technical requirements in the field of hygrothermal characteristics consists of monitoring numerous parameters of an entire building, and in particular of its partitions and their joints and building systems. Therefore, the paper presents calculations regarding determining the material systems of building partitions and building joints with the use of professional software. The main part of the article is to establish the impact of energy-saving technologies on the energy consumption of the newly designed buildings, but also of the buildings that are undergoing modernisation processes.