In recent decades, the sustainable development of the planet has been negatively affected by a number of factors, including the construction industry. The construction industry includes, among other things, the highly topical energy reconstruction of existing prefabricated residential housing, which is implemented to improve their condition from a thermal engineering and energy perspective. Composite materials, known as external thermal insulation composite systems (ETICSs), have come to the fore, bringing a number of undeniable benefits to society. After more than 20 years of experience, it turns out that in addition to the benefits, ETICSs also bring new research challenges to the discussion, which are related to the issue of the biocorrosion of the external envelope of ETICSs, and also to the issue of the indoor microclimate. Based on the literature review and case studies, we aim to show that ecologically friendly building materials require a multidisciplinary approach. At the same time, we want to contribute to the discussion of whether the diversity of microorganisms on ETICS composites is a potential source of health risks and whether the transport of microorganisms to the indoor environment can be ruled out through natural ventilation from the outdoor environment to the interior.

Influence of thermal bonds when evaluating the energy performance of buildings can be included in the calculation approximately by means of a surcharge on the effect of thermal bonds or precisely by using specific linear heat transmission coefficient for thermal bonds between structures. The article presents a comparison of the two options in the energy performance of a particular building, the specific amount of heat for heating the building of a brick passive house based on the foam glass.

Foam glass granulate is environmentally friendly, heat-insulating building material which is made from recycled glass waste. It is a very porous material with low density, with good thermal insulation properties, high static load capacity and almost zero water absorption. The paper deals with the research of the temperature field process in the soil under the floor of a passive house built on a reinforced concrete slab foundation with a layer of compacted subsoil using raw materials friendly to the environment in the form of granules of foamed glass. This method of progressive foundation of the building addresses the elimination of thermal bridges at the base and establish a continuous thermal insulating of the building envelope without thermal bridges.

The analysis focuses on the influence of boundary conditions on the final energy intensity of selected groups of houses. The individual energy intensity will be set for the selected buildings. For these buildings, the standard boundary conditions will change (indoor air temperature). The deviation values of resulting energy consumption will be defined by statistical evaluation.

The evaluation of non-renewable primary energy expressing the impact of the environment is part of the energy performance certificate. The evaluation is based on factors of primary energy. New buildings or larger modifications of existing buildings must meet the legislative requirements in the Czech Republic, which are consistent with the requirements of the European Union. On the basis of modeling of different energy sources and different number of energy sources for the selected building are set values of non-renewable primary energy.