The construction industry is considered an activity responsible for both significant CO2 emissions and material flows. Providing affordable, decent, and sustainable habitats is, however, a fundamental human need. Therefore, the chapter aims to analyse the environmental impacts of construction and energy upgrades of detached family dwellings typical in Hungary. For the analysis of environmental impact, the concept of ecological footprint (EF) was used. The main advantages of this method are that (1) results can be compared to the upper limits of sustainability, (2) figures are rather easy to understand for each stakeholder, and (3) the concept may take into consideration all impacts of human activities. The chapter, however, analyses only the EF of material use of constructions. The sample consists of data on five detached family houses, representing the housing in Hungary: (1) a new two-storey family house with a gable roof, (2) a new family house made of timber, and (3) an energy upgrade of a typical family dwelling built between 1950 and 1990, called “Hungarian cube”. The results show that the construction of new detached family dwellings has a significantly higher ecological footprint than renovating an existing one. Using non-conventional construction materials (e.g. timber), however, can decrease the ecological footprint of construction, but useful lifetime should be considered more deeply in this case. Volatile energy prices have highlighted the importance of the energy efficiency of the housing stock. Newly built dwellings have outstanding insulation and, therefore, have nearly zero emission during operation, but they are not the means of affordable housing due to their construction costs, and the construction itself has a significant environmental impact which is not outweighed by the energy savings during the useful lifetime. Therefore, retrofitting and even extension of dwellings can better contribute to the Sustainable Development Goals (SDGs).

Greening tram tracks has ecological, urban planning and economic impacts. Greening of the tracks supports the development of sustainable stormwater management as well as improving the visual appearance of the city. The restoration of the natural water cycle is achieved through water-sensitive design: the innovative solution used achieves both the retention of water, the reduction of run-off and the increase of the surface area available for evaporation. The literature data (Grüngleis Netzwerk, 2011) show that 50-70 % of the annual precipitation projected onto the green runway is absorbed and re-evaporated. The urban climate impact of the vegetation systems to be developed is most pronounced in the summer months. The microclimate of green track environments has a positive impact on the health of the population. Our work will investigate the effects of green vegetated areas. In this study, we analysed the ecological impact and the capacity to sequester of carbon dioxide from the atmosphere by photosynthesis of grass- and crowfoot-lined tracks. The Sedum green roofs quantified carbon storage is approximately 160 gC/m² during a two-year period (Collazo-Ortega et al., 2017). The concept of a vegetated track leads to an improvement of green space indicators in a complex system of urban environments through the correct choice of vegetation plants. Prioritising and encouraging the construction of green tracks is one of the possibilities to make the urban environment more livable. It is also necessary to encourage this at the regulatory level in cities.