This book is based upon work from COST Action TU 1403 adaptive facade network, supported by COST (European Cooperation in Science and Technology). COST is a pan-European intergovernmental framework. Its mission is to enable break-through scientific and technological developments leading to new concepts and products and thereby contribute to strengthening Europe’s research and innovation capacities.
The unique feature of adaptive facades is their capability to adapt physical properties (i.e. thermooptical, structural, etc.) in a reversible way as a response to and/or to adjust to transient boundary conditions (either external, such as climate, or internal, such as occupants’ requirements), in order to respond to changing priorities (i.e. minimizing the building energy use, maximizing the use of natural light, etc.). The term ‘adaptive’ is often synonym to ‘responsive’, ‘dynamic’, ‘switchable’, ‘smart’, ‘active’ etc. Adaptive facades are a collection of very different systems that are evolving rapidly, and their rate of innovation is not easily followed by the development of the entire set of methods and tools necessary to comprehensively evaluate their performance.
In such a context, the performance characterisation of adaptive facades is a challenging task because of a multitude of intrinsic and extrinsic reasons. The intrinsic complexity of the dynamic behaviour of these systems, when compared to traditional building envelope components, leads to the fact that conventional simulation tools, experimental assessment methods, and key performance indicators cannot be fully adopted in the case of adaptive facades. Procedures for simulations and experiments, and corresponding assessment criteria are still evolving. The research community is therefore actively engaged in the definition of the necessary standardised approaches which can support the integration of adaptive facades in buildings.
The contents of this book reflect the efforts carried out in the framework of Working Group 2 (WG2) of the COST Action TU1403 Adaptive Façades Network, “Components performance and characterisation methods”, in the search for fundamental knowledge to establish robust and shared methods, techniques, procedures and tools for the characterisation and performance evaluation of adaptive, multifunctional facades, at façade component and system levels.
The development of adaptive façade systems and materials, as well as their penetration in the construction industry, can be accelerated with the use of modeling and simulation. Performance prediction using computer models can for example be used to investigate the impact of different adaptive materials or façade configurations on economic and environmental building performance, to assist in the optimization of dynamic façade control strategies and/or material design. When this is done in an appropriate way, it can make significant contributions to improving indoor comfort, design robustness, reducing energy use and improving energy flexibility of buildings.
Building performance simulation (BPS) is a well-established research discipline and a widely used design support tool in the field of building engineering. Several models for adaptive façade technologies had already been developed when the COST Action started. However, the performance prediction of adaptive facades is considered a challenging task. This is partly due to the fact that information on this topic is scarce and fragmented. There is very little guidance for newcomers about what modeling strategies they can best use to tackle the adaptive façade project they have at hand.
This first section of the book presents a critical review of the modelling methods, requirements and capabilities of current building performance simulation tools to accurately quantify the performance of adaptive facades. This is targeted at researchers and professionals interested in modelling a specific technology or evaluating a range of performance indicators, and/or to Master and PhD students who are approaching the problem of quantifying, in a numerical way, the effect of an adaptive façade on the built environment.
In the second section, the challenges represented by the characterisation through experiment of the behaviour of adaptive façade are presented: the aim of this section was to collect and analyse the different possibilities for testing adaptive facades available at the institutions of the participants in the COST Action.
The third and concluding section reports the results of the activities investigating how the performance of adaptive facades can be described and communicated by the use of suitable metrics.