| Abstract [eng] |
Each year the energy consumption in residential buildings is increasing. It causes negative environmental impact because a great amount of resources is required to fulfill energy demand for heating. However, in majority of the building’s energy loss is high due to thin insulation layer in the walls and roofs, obsolete technology of the windows, lack of recuperative devices. Furthermore, according to the current construction law each construction that is planned to start in 2021 or later will be required to meet A++ energy efficiency class requirements or higher. In recent years the environmental friendly ideas are bocomming more and more popular. Building of energy efficient buildings is one of them. In these houses heat insulation and effective energy consumption is of the utmost importance. However much more building materials are required to build a house of higher energy efficiency class. So, it is important to evaluate if a building of higher energy class is causing less environmental damage in the long run. First, I analysed house models that meets A++, A+, A, B and C energy efficiency class requirements. Then I compared the results of the life cycle assesment for diffenten classes. Using characterisation and normalisation resuts I determined that lower energy efficiency buildings cause higher negative effect to the environment despite of the grater usage of construction materials. The highest negative effect is caused by the electricity required for household appliances, energy for regulating the heating, ceramics and mineral wool. From normalisation results one can see that these factors cause greatest impact on the resource category. The lowest effect is observed on the ecosystems. The total effect of the energy consuption and total effect of the building materials to people healt was compared. For the A++ class building energy consumption effect was greater than that of materials by 8.9, while for C class building this ratio was 14.8. In ecosystems category the ratio for A++ class was 8.1 while for C class building the effect ratio was determined to be 24.8 times. In resources category the ratio for A++ class was 89.4 while for C class the energy consumption effect was 37.1 times greater than the effet of construction materials. Life-cycle assessment shows that the most significant impact, irrespective of energy efficiency class, is energy consumption: thermal energy consumption and electricity for household appliances. The most negative impact of building materials is on ceramics and stone wool. |
