Climate Adapted Façades in Zero-Waste and Cradle to Cradle Buildings – Comparison, Evaluation and Future Recommendations, e.g. in Regard to U-Values, G-Values, Photovoltaic Integration, Thermal Performance and Solar Orientation

The construction methods we are using today on a broad scale are highly unsustainable in regard to their resource efficiency. Fundamental improvements are necessary in order to change towards a more ecological future. The integration of reusable building components could be an adequate option to significantly reduce the ecological deficits we are facing today. The concepts of Zero-Waste and Cradle to Cradle are seen as viable solutions for the future. The few already existing Zero-Waste and Cradle to Cradle buildings are currently representing the most advanced construction standards of resource efficient design. In regard to their façades, however, there is still a high improvement potential. Therefore, methods have been elaborated within this research which demonstrates how the façades of Zero-Waste buildings can be strongly optimised. In particular, this research poses the question: with which interventions can we improve the performance of façades of Zero-Waste buildings? Which interventions are most important and how can we prioritize them? For example, which role does the insulation capacity of the building skin play in comparison to the building’s capability for natural ventilation and external shading? Within this paper, at first, the façades of selected existing Zero-Waste and Cradle to Cradle inspired buildings are examined and critically evaluated in regard to their u-values, g-values, photovoltaic integration, thermal performance and solar orientation. Furthermore, criteria such as sun exposure of glazed areas, natural ventilation capacity through façade openings etc. are investigated. Thereafter follows an assessment in the form of a list about which interventions could significantly improve the façade’s performance in regard to energy efficiency. The approaches include active strategies, such as improving the u-values, photovoltaic energy generation and passive strategies, such as enabling natural ventilation through the façade and external shading of sun exposed glazed areas. The selected case study buildings in Germany are “Aktivhaus B10” in Stuttgart by Werner Sobek, “Woodcube Building” in Hamburg by IfuH Architects and Architekturagentur, “ICON Rheinlanddamm” in Dortmund by William McDonough and Partners. In order to recommend which interventions are the best applicable in the relation between ecological performance and cost, the paper concludes with a prioritisation of the suggested improvement options. Overall, it demonstrates that the building’s overall energy performance can be significantly improved by adapting the façades towards a better implementation of passive strategies which take strong advantage of the project site’s individual climatic conditions.