Aging residential buildings in urban areas require effective thermal insulation to enhance energy efficiency and indoor comfort. In Bosnia and Herzegovina (BiH), expanded polystyrene (EPS) is the most commonly used insulation material due to its affordability, despite concerns regarding its flammability and environmental impact. While regulatory changes since 2019 have recommended rock wool for high-rise buildings, the absence of binding fire safety regulations has allowed the continued use of EPS, often driven by financial constraints. This study examines energy efficiency refurbishments in Sarajevo’s high-rise residential buildings and analyze the implications of the partial implementation of recommended measures. Using case studies, surveys, and expert interviews, this research identifies key challenges, such as limited funding, fragmented renovations, and inconsistent coordination between stakeholders. The findings indicate that facade insulation is often prioritized over comprehensive upgrades, including window replacement and heating system improvements, leading to suboptimal energy savings and minimal cost reductions for residents. Additionally, the complexity of multi-apartment ownership structures hinders uniform improvements in energy efficiency. Despite these challenges, property values tend to increase after renovation, highlighting the long-term financial benefits. To maximize energy savings and ensure sustainable urban housing, stronger interdisciplinary collaboration, improved funding mechanisms, and adherence to fire-safety standards are necessary. These measures would enhance the effectiveness of renovations and support long-term energy efficiency strategies.

Contemporary neighborhood livability differs across countries due to implementation of sustainable policies within the building sector. This paper aims to showcase these differences among Germany, Croatia, and Bosnia and Herzegovina through a comparative case study analysis of two contemporary housing developments from each country. Representative neighborhoods from the aforementioned countries that were selected for analysis were located in Munich, Rijeka, and Sarajevo. The residential environment livability analysis method was used in order to pinpoint and compare results of each of these cases, and to assess their livability. The highest number of livability criteria among analyzed cases were found in Munich, while the lowest were found in Sarajevo. The conclusion is that this is happening due to German authorities actually implementing sustainable building standards in housing development prescribed by sustainability policies, while the authorities of Bosnia and Herzegovina completely, and Croatian authorities partially, go around these policies and bend to the will of investors, regulating residential urban development to the detriment of end users.

BACKGROUND Indoor air quality (IAQ) in classrooms affects children's health and academic perfor-mance. The aim of this pilot study was to determine IAQ in elementary schools different in their inter-nal and external characteristics, in settings of COVID-19 epidemics. METHODS IAQ parameters: fine particulate matter (PM2,5) mass concentration, CO2 concentration, tempera-ture and relative humidity were measured in parallel in four elementary schools/classrooms during October (non-heating season) and four months (including holiday in January) of heating season. IAQ parameters were measured in settings of anti-epidemic restrictions (≤13 students in classroom, frequent ventilation). RESULTS During October, except in one school, PM2,5 concentrations were below the upper recommended value (25 μg/m³), but started rising in all schools in the heating season. The highest concentrations of PM2,5 were registered in two schools with closed or shortly opened windows. CO2 concentrations were mostly in the recommended range (up to 1000ppm) except in the school with constantly closed windows and in three schools in February when concentrations were higher. Except in one, the same school, and in January, both temperature and relative humidity were out of the recommended range (24,0-27,0°C in non-heating; 20,0-24,0°C in heating season; and 45-55%), with temperature mainly above and relative humidity mainly below it in three schools. The largest deviation in temperature and relative humidity were registered in urban schools. Registered differ-ences may be explained by different internal and external characteristics. CONCLUSION Despite anti-epidemic restrictions, most of the measured IAQ parameters were out of the recom-mended values in heating season. In addition, further deterioration of IAQ could be expected if all students had been presented in the classroom. Finally, to assure a healthy school environment in heating season, further optimisation of both indoor and outdoor conditions is needed in both pandemic and non-pandemic settings.

Presently, almost all human activities (agriculture, transport, industry, construction sector, etc.) have an adverse impact on the environment. The construction sector in the EU alone accounts for a big part of the total energy consumption and emission of CO2. Two-thirds of the energy used in the construction sector in Europe goes to housing. As the number of residents grows, the requirements for new housing increase, causing an additional increase in energy consumption and new CO2 emissions for construction, maintenance, lighting, ventilation, cooling, and heating. Benefits of detailed planning of sustainable development of the construction sector are manifold. The most important benefits are sustainable use of resources, economic and social development of communities, increasing employment rates, improvements of living conditions and protection of the environment. Two scenarios for the development of an energy-efficient construction sector in Bosnia and Herzegovina with a focus on housing facilities are developed, in order to address the needs and benefits of detailed planning. Both scenarios analyze the effects on job creation, the impact of used construction materials on the environment and eco balance of local products. The difference in the solutions confirms the benefits of an interdisciplinary approach to the planning of sustainable systems so that not only technical, but also economic and social benefits can be evaluated thanks to the combination of methods used.