Building Envelopes Embracing Design Technology
Visual mosaics of building envelopes form skylines and aerial frames of our cities today. Conceived in varying scales, shimmers and ages, to envelope a building is to add visual identity, character and expression of architecture to the context, and the city at large.
Design and aesthetics of building skins impart a character to a place, externally, and is a major parameter for building performance, internally. Filling up this liminal frame separating the two efficiently requires an integrated practice of rational and intuitive approach, which is executed as a design & engineering process. This is where disciplines merge and science meets art in a collaborative laboratory environment. Such a joint effort is to carefully synchronize how the 'built' is to be cloaked from the world around, or if at all.
A building skin consists of vertical (facade) and horizontal (roof) components which protect the building from direct external environment and helps in maintaining comfortable interiors along with providing structure and stability to the building. Building skins are a vital component to resolve issues of responsive architecture as they are a medium through which intelligence can be imparted to a building system to respond to an environmental stimulus. Thus, key characteristic of an effective intelligent building skin is its ability to modify energy flows through the building envelope by regulation, enhancement, attenuation, rejection or entrapment.
A building skin is designed using a number of parameters such as environmental conditions, structural feasibility, and materiality, among others; all of which can be quantified as data. Since there is a large amount of data involved, computation becomes an essential part of dealing with the complex dynamics of design. Computation can be carried out through non-digital & digital processes aligned together and algorithms can be used of complex (and simple) problem solving. These problems include structural load calculations, material behaviour calculations, fabrication data extraction, etc. An algorithmic method of designing a building skin or a façade system can aid in controlling all the parameters and objective data that is embedded in design and a flexibility to use this data for creating a smart(er) system.
Figure 1: Relationship of internal conditions, climatic conditions and building skin
Urban collage of building envelopes is rooted into interdisciplinary methodologies, with collective fields moderating and analyzing range of extreme variables/factors present at both sides of envelopes, in a laboratory-inspired culture. The goal is to create skin-systems that have unbiased and durable response to both external and internal stimuli.
To ease the process, intersections of mathematics and computer science help propose use of algorithms that are self-contained step-by-step set of operations to be performed. Algorithms exist that perform calculation, data processing, and automated reasoning. In façade design, an algorithmic approach is helpful to have a rational control on design, fabrication data, assembly process, material usage & cost. Design can be optimized for various criteria and one type of algorithms that can be used for multi-parametric problem solving is 'Genetic Algorithm'. A parametric model is controlled by multiple parameters which can be used as 'genes'. The set of parameters form the 'genotype' and output system forms the 'phenotype'. Genetic algorithms are used after understanding the complexity of the multi-parametric problem to build an iterative system. Genetic algorithms are used to create a strong feedback network in the algorithm where real-time evaluations inform the initial stages of the algorithm.
Figure 2: Parametric Façade for Molded Dimensions Factory, Gurgaon, designed by rat[LAB] in collaboration with Design Plus, New Delhi
In an on-going project by rat[LAB] in collaboration with Ar. Abhishek Bij of Design Plus, New Delhi for Molded Dimensions Factory, Gurgaon, a prominent part of the façade is designed to create an aesthetically dramatic effect, while optimizing building performance and fabrication cost. A differentiation among members of façade is being parametrized through an algorithm that calculates the running length & cost of various building members. This allows to change the base parameters (such as angular variation, dimensional shifts, etc.) and study its changing effect on fabrication cost & environmental performance. Multiple platforms are integrated to evaluate the results in real-time, as we change the influencing parameters and create a range of designs. This allows choosing an optimum design for the façade, based on the set criteria. The algorithm is also developed to extract fabrication data from the parametric model, saving on design & production time, hence cutting down on project costs.
Figure 3: Parametric Façade for Molded Dimensions Factory, Gurgaon, designed by rat[LAB] in collaboration with Design Plus, New Delhi. A computational workflow is followed in design process to extract fabrication data and environmental analysis of façade parametrically.
An international collaboration of rat[LAB] with Takumi Yoshioka and Masaki Morinobu of Nonscale Co. Tokyo led to a proposed shopping centre for Japan & India exhibited at the SC Fair 2016 held at Yokohama, south of Tokyo, in Japan. The project is designed by Nonscale Co., while the highlighting roof-structure has been envisaged and designed by rat[LAB]. This large span adaptive roof structure inherits hybrid qualities of a tensile and a grid shell, with automated shading devices inbuilt in the structure. The project explores Computational Techniques to develop Form, Structure & an Adaptive Skin /Envelope for the Architectural Built. Advanced Computational Techniques & Methodologies have been used to design a complex roof structure that can adapt to dynamic environmental conditions. The multi-functional shopping centre will be sheltered by a large span skin which incorporates origami shading modules with a transparent material for a visual connection. It will be a shopping centre ventilated like any outdoor space with controlled temperature and better comfort levels.
Figure 4: Long-span Tensile-Grid Shell (SC Fair 2016, Yokohama)(Sketch & Visualization by Nonscale Co. Ltd. Tokyo, in collaboration with rat[LAB])
Figure 5: Environmental Analysis (SC Fair 2016, Yokohama)
Cellular Morphology Façade, again an ongoing exploration by rat[LAB], is digitally retrofitted on S-W façade of the tower and consists of multiple unique components of hexagon topology. The hexa-grid system is controlled through an algorithm that alters its density and attraction during the concept design stage. Six prominent functional zones are speculated as attractor points on the façade that become the first parameter of control and Solar insulation analysis on existing S-W façade becomes the second guiding parameter. With the new morphology of this retrofitted façade, local angular variations are introduced that can redistribute the sunlight in a differentiated manner on the building envelope. This can potentially change the way building is heated up and gets daylight in the interior spaces. Light, heat & visibility of / from interior space can now be optimized as per user requirements, adding a locally embedded intelligence in the new façade geometry. These parameters can be tied up with LEED / GRIHA factors so as to work well with the industry norms too.
Figure 6: Comparison of existing and new façade system through solar insolation analysis (Original Photo Copyrights: Deepak Chandok ; Visualization: rat[LAB]-Research in Architecture & Technology)
Figure 3: Prototype of Cellular Morphology Façade exhibited at Alliance Francaise de Delhi, February 2015
The most interesting one (and challenging too) has to be 'adaptive [skins] or 'adaptive [systems]' project. It is a project that was started in London as part of an academic research and build upon it in various iterations in Los Angeles later on. It was started with a sole vision of challenging the static built environment against the dynamic natural environment, where numerous layers of architecture come together to make a building function in negotiation with changing environmental parameters such as sun, rain & wind. The research has taken a series of iterations from 2012 to 2014, with the latest developments shaping up in Los Angeles, CA at The MAK Center. A dynamic façade system was designed as a proposal for MAK's Exhibition Space at the site of Mackey Apartments, which was designed by one of the pioneers of Modernism – Rudolph Schindler in 1939.
Figure 7: Proposal for dynamic façade at MAK’s Exhibition Space in Los Angeles, California
rat[LAB]'s ongoing projects across India exploring various building envelope iterations include KUN Aerospace Factory project in Chennai, where identity and sustainability have been looked into through a context-based computational approach. The envelope developed embraces the flows in nature, and moulding itself to new creations in an inspired manner. Instead of barring wind flows for example, this facade is designed using the same flows as technical data as well as guiding curves which define the very skin of the built form, at the same time inspired by double curved geometrical industrial parts manufactured in this building.
Figure 8: Conceptual visualizations of computationally designed façade for KUN Aerospace Pvt. Ltd., Chennai; an on-going project by rat[LAB].
Building skins lie at intersections of exterior and interior environment. An opaque separation or vitric façade/skylight doesn't accurately answer to our most intricate questions on building envelopes. Computational methodologies of deriving, analysing and streamlining contextual data from the building vicinity initiates a shift in this conventional process. Scientific knowledge is then imbibed by designers and artists to make tangible and sustainable skin-systems, forming an integral part of building aesthetics as well as building performance. Such an approach would paint a better meaningful picture of our city skyline.