Starting point and motivation
Human-made constructions and biological systems for protective covers are exposed to the same environmental conditions and needs. Hence, the requirements to skins or shells in the nature and envelopes of buildings are comparable.
Considering that the façade has the largest surface area of the building envelope, it also holds a substantial potential in gain and loss of energy and comfort. Modern façades shall not only protect from unwanted influences, but also utilize solar energy, provide high thermal and visual comfort, and control daylight and fresh air inlet. Last but not least, they shall take the aesthetic, psychological, physiological and social needs of inhabitants into account. These complex demands put a great technical challenge on facades, but also show the great potential for saving energy and reducing CO2 emissions. The search of new and robust solutions for – long term spoken – truly sustainable facades, which combine maximum energy efficiency and comfort with minimum resource consumption and embodied energy is the leading motif of the basic research study BioSkin.
The energy balance between the internal and external environment is a constant adapting process that can be utilized for a better efficiency performance.
Scope and objectives
The objective of the basic research study is to utilize the potential of the cross-disciplinary acting discipline Biomimetics to identify innovative solutions for new facade designs. The search in the large diversity pool of nature is directed by target indicators for the facade of the future: Integrative multifunctionality (embedding functions in material-structures), self-regulating adaptation (self-activating adaptability), and conservation of resources and localization (local usage and application optimization of materials).
Methodological approach
For the study, the core mission of Biomimetics – to learn from nature – and the top-down principle (analogy research) has been applied. It investigates on the basis of formulated “biologized” questions respective analogies in nature, identifies their functional principles and evaluates their transmission capability for multifunctional facades. Promising biological principles are then subsequently transferred by several abstraction and selection steps into new (biomimetic) technical concepts.
The evaluation of the gained results has been accompanied by an innovation process and by an internationally renowned, interdisciplinary team of experts from biomimetic architecture, facades, chemistry, biology, materials science, botany and ecology along the project duration.
BioSkin process – Top Down method, that focuses on functional goals to achieve by investigating potentials in nature.
Results and conclusion
Based on the survey of the status quo of existing energy efficient façade solutions and trends for the future, 40 target criteria have been defined and translated from technical descriptions to abstract quality requirements. These requirements have been conferred to “biological questions” to carry out extensive research on potential biological role models. In total, some 240 biological organisms are identified with a transmission potential for facade functions. 43 role models have been incorporated into biological data sheets summarized as “BioSkin data” – Annex 2.2. and 2.3. (partly in German).
Annex 2.2 offers a list of identified organisms and Annex 2.3 shows data sheets of selected organisms in an ordered structure to illustrate their functional and biological characteristics.
Extract of the “BioSkin creative card” – functional principle of the sea orange / Daylight harvesting and distribution
In the final step of the study, about 30 data sheets have been chosen as basis for the development of 37 biomimetic facade concepts. Four biomimetic concepts have been considered for further numeric analyses to evaluate their application potential in defined scenarios including building types, thermal qualities and different climate locations.
The final report and the Annexes “facade requirements” (facade principles matrix), “collection of potential biological role models” (BioSkin database) and “biomimetic façade concepts” (best case models) are available on the funding website Haus der Zukunt Plus on open source basis to enable more interdisciplinary research and development (Report is in German).
The results of this study shall provide information for interdsiciplinary research on innovative energy-efficient façade technologies, and shall encourage cooperations on emerging technologies in the construction industry.
Future prospects
The positive feedback from the dissemination activities and the extensive data collection triggered high interest in the results of the BioSkin study.
The developed evaluation and selection process provides useful methods and tools for the challenges of interdisciplinary work between technical and natural sciences. Hereby, parts of the developed methodology are contributed to the VDI-Standard: VDI 6226 -1: Biomimetics – Architecture, civil engineering, industrial design – Basic principles. Some of the results are contributed to the book: Biomimetics for Architecture & Design.Nature – Analogies – Technology. (Pohl, G., Nachtigall, W.), Springer International Publishing, 2015.
The project has been conducted by: DI Susanne Gosztonyi, Dr. Florian Judex, DI Markus Brychta, Stephan Richter BSc, AIT Austrian Institute of Technology, Energy Department, Sustainable Building Technologies and Dr. Petra Gruber, transarch - office for biomimetics and transdisciplinary architecture Valuable support has been provided by the international expert team: Prof. George Jeronimidis, University of Reading, Centre for Biomimetics, UK Prof. Thomas Speck, Universität Freiburg, Kompetenznetz Biomimetik, BIOKON, DE Dr. Susanne Geissler, Austrian Energy Agency, sustain, AT Prof. Sergio Altomonte, University of Nottingham, UK The creative concept developments have been a process result of some workshops within the project team, with many engaged colleagues from the AIT Energy Department, and students from the Applied University of Technology Technikum Vienna (MEE). The project is funded by the programme "Haus der Zukunft Plus" within the framework of the Austrian Research Promotion Programme, provided by the Federal Ministry for Transport, Innovation and Technology (BMVIT).