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• Low energy use of single-family buildings can be assured solely by passive design. • Passive adaptation only partly counterbalances climate change effects on energy use. • Total energy use will decrease in cold and temperate and increase in warm climates. • The most effective long-term climate adaptation measure is applying smaller windows. • New buildings should be designed according to mid-term optima (2020/2050 period). The presented study aims to clarify the implications of passive design measures on heating and cooling energy use of single-family residential buildings under European representative climates. In order to address this matter, different values of thermal transmittance (opaque and transparent), window to floor ratio, window distribution, shape factor, diurnal heat storage capacity, external opaque surface solar absorptivity and natural ventilation cooling rates were combined in 496,800 building energy models, which were simulated at eight locations. Because buildings are in use for many decades, the energy use simulations were made considering the projected climate change up to the end of the 21st century. The results delivered a set of the most effective passive design measures for achieving low energy use in buildings regarding climate type and period. A lower window to floor ratio was identified as the most universally applicable design measure to counterbalance the projected effect of a warming climate. In contrast, other measures vary according to climate type and studied period. Furthermore, it was concluded that it is difficult to neutralise the projected climate change effects on buildings' energy use, even when applying the best performing combination of passive design measures. However, reasonably low energy use can still be assured solely by passive building design, especially in oceanic, warm, and some temperate climate locations. Therefore, the identified trends in energy use and passive design measures represent the foundation for strategies and guidelines aimed at future-proof energy-efficient buildings. [ABSTRACT FROM AUTHOR]

Due to the profound impact that building sector has on the environment and consequently the sustainability of our society, the evaluation of environmental impacts through life cycle assessment (LCA) should become part of building design. The number of published environmental product declarations (EPDs) is growing, which indicates that they can become valuable tools for building designers to evaluate the environmental performance of construction works. We identified that in the current EPD scheme an important part is missing – the results interpretation. In order to evaluate the environmental performance of buildings or their components and elements, the designer is "forced" to conduct a comparative assertion on a population of alternatives. The paper explores the results interpretation of LCA data in the context of the EPD scheme for building products and presents a comparative assertion method, which could guide designers through the results interpretation step of LCA. The proposed soft comparative assertion method was tested on a sample of external wall assembly alternatives and the results show that it significantly simplifies the LCA results interpretation and enables straightforward decision making. However, the method is not yet a fully functional tool and should be upgraded in order to make the decision process more robust and less subjective. With this paper we wish to encourage further research on the described topic, which is vital in order to add credibility to the EPD scheme as an instrument for lowering the environmental impact of the building sector. • Evaluation of environmental impacts by LCA should become part of building design. • Comparative assertions required in order to evaluate LCA data from EPDs. • No guidelines for building designers at the LCA results interpretation step. • Presentation of comparative assertion method framework for building designers. • Developed method significantly simplifies the decision making process. [ABSTRACT FROM AUTHOR]

In recent years the use of wood based products in building industry has expanded. Although lightweight timber constructions essentially decrease environmental impact of a building, their consequential low thermal mass can lead to overheating during summer. Therefore, the purpose of this paper was to investigate various examples of enhanced lightweight constructions from the thermal response point of view. Several improvements were investigated (e.g. clay boards, wood wool thermal insulation, Phase Change Materials, etc.) and compared with the performance of a conventional thermally insulated high mass wall. Finite element model was created and dynamic thermal performance of enhanced lightweight external walls was analysed in three different European locations: Helsinki (Finland), Vienna (Austria) and Madrid (Spain). Certain enhancements resulted in lower internal surface temperature of constructions up to 1 °C, depending on location. In addition, it was shown that in order to further improve thermal performance, application of high intensity ventilation is necessary, which additionally lowered the internal surface temperature up to 8 °C. It was shown that enhanced and naturally cooled lightweight constructions are more suitable for locations with milder summer temperatures (Northern, Central Europe), rather than for hot climates (Mediterranean). It was concluded that the application of lightweight constructions should be thoughtful in order to achieve adequate thermal response of buildings. However, in lightweight buildings the integration of materials characterised by high thermal mass, high thermal effusivity and low environmental impact should be encouraged. [ABSTRACT FROM AUTHOR]

Quality of indoor environment as well as energy consumption in buildings are a growing concern in the context of overheating of buildings, as the EU legislation is primarily focused on heating season. The statistical data of EU have shown that there is already a large amount of buildings not comfortably cool during summer and the trend is increasing. Therefore, the main goal of this paper is to evaluate the influence of high intensity passive cooling as one of the passive solutions for overheating of buildings on the overall thermal response of building envelope systems. Specifically, a variety of multi-layer external walls during realistic summer time conditions of Central European climate were considered. For this purpose, a finite element method was used to simulate the non-stationary thermal response of several heavy weight and light weight external wall constructions. The results have shown that indoor air change intensity as well as internal heat gains have a significant impact on heat flow through the building envelope. Clear difference in thermal behaviour was detected between light weight and heavy weight envelope systems, as a consequence of different thermal mass and thermal insulation position. While the results of the conducted study represent guidelines to architects, designers, investors and other stakeholders in building industry, the growing popularity of light weight constructions, especially in residential buildings, dictates further research of building envelope configurations and passive cooling system impact on the thermal response of constructions. [ABSTRACT FROM AUTHOR]

• Adaptive thermal comfort field study was conducted for subjects at a high metabolic rate. • About 92% and 68% students were found comfortable during autumn and winter season, respectively. • Accepted mean airspeed for male was higher than female (AVSm = 0.29 m/s; AVSf = 0.17 m/s) • Seasonal comfort temperature varied by more than 5°C. • Subjects are found to be more sensitive towards outdoor temperature fluctuations. An adaptive thermal comfort study was carried for assessing the thermal comfort requirements of students working in naturally ventilated (NV) university workshop building in the composite climate of India over two seasons (Autumn and Winter). 1332 complete surveys, 516 and 816 from autumn and winter season, respectively were collected and analyzed. A maximum of 70% of subjects were found voting comfortable when indoor temperature varied from 28°C to 32°C. During the autumn season, the mean comfort temperature was about 5°C higher than the winter season. Also, female subjects had about 1.5°C higher comfort temperature compared to male subjects. Further, an attempt has been made to present an adaptive model for university students engaged in activity corresponding to machine work. The results were also compared with international thermal comfort standards. The results showed that students are more sensitive towards the fluctuations of outdoor conditions compared to the subjects in office and residential buildings. Moreover, subjects have shown better thermal adaptability towards prevailing mild cold climatic conditions through behavioural and clothing adjustments. [ABSTRACT FROM AUTHOR]