Façade and windows are evolving with new materials, not to forget enhanced safety measures during installation.
By Jayashree K M
We live in the day and age of smart materials which are transforming the way people think about how buildings should be designed, built and powered up. There is minimalism that is clashing with ostentatiousness, simple with the complex, and traditional with the modern. Architects and façade contractors are furiously working at embellishing buildings with elaborate façade and window designs that are supposed to inspire while creating shock and awe.
Simultaneously, the façades and windows that are being fitted must have high impact and bending resistance, tensile strength and resistance to mechanical damage, abrasion resistance, high resistance to chemically aggressive environments and organic solvents, high density, (imporosity), among other things. Importantly, it must be near zero absorption, i.e. the material should not absorb moist. When you have stipulations like these, it’s necessary that façade contractors understand every aspect of materials, their phenomena, and reactions to unexpected situations.
Considering that people want novelty in all they buy or see, it’s no surprise that new materials are emerging in façade and windows too. Navin Keswani, MD, Aluplex, says, “The infill materials used in façades include glass, aluminium, copper, stainless steel, stone, corten steel, ceramics, porcelain, natural stone and GFRC. The newer materials used as infill panels include BIPV (Building Integrated Photo Voltaics) as façade panels- wherein the infill material used in the façade not only reduces energy costs by allowing light and resisting heat gain but also produces energy by integrating a photovoltaic cell within the laminated glass. The façades are designed to incorporate the same with the necessary electrical connections.”
Façade of the building is more than what meets the eye. Façade elements have been constantly evolving over the ages and adapt to changing environment and aesthetic sensibilities. “Occupants prefer façade materials that have functional benefits as much as visual appeal. In that respect high pressure laminates are being reinvented time and again and are now preferred for buildings that require niche and sophisticated look. The Max Exterior panels from FunderMax are installed using rear ventilated system which enhances the energy efficiency of the building. It is available in multiple colors that provide design freedom and adds character to the buildings,” says Dr Prashanth Reddy, MD, FunderMax India.
Certain materials that had useful purposes for other aspects other than façade have creeped in here too. Kapil Chikodi, VP, business development, Glass Wall Systems, says, “We have begun experimenting with porcelain tiles for one of our projects. Hitherto, these tiles were used for flooring and internal interiors, but now makers are also manufacturing exterior porcelain tiles. This offers a clean façade, is maintenance-free and also economical. There are honeycomb panels also emerging in India, which have good properties of insulation. These panels come with a composite material of stone slates and overall offer a natural look.”
Glass Wall Systems has used this at its Kingfisher Tower project with Lilli System from Italy.
Over the years, materials have evolved for façade and windows. “There are plenty of new kinds of material used in façades these days but glass is the main component. New kinds of glasses are sage glass and dichroic glass. Incidentally, we are doing our first project with sage glass on façade Monte Carlo corporate house in Ahmedabad and first project with dichroic glass Parinee I,” says Kapil Shukla, MD, KK Holding.
In the recent times, the high pressure laminate is increasingly gaining acceptance. Varghese PV, CEO, Sobha Glazing & Metal Works Division, says, “After the revision of the National Building Code, people are looking at fire-rated Aluminium Composite Panel (ACP) and solid aluminium sheet cladding in place of normal ACP. When it comes to glass, the latest trend is sage glass, which can be converted into graphic screens with the click of a remote button. However, this is an expensive option. In addition to this, screen printing on the glasses of façade is also gaining traction.”
Since windows and doors is the forte of Geeta Aluminium, the company believes in constantly revamping its products. Atin Thacker, marketing director, Geeta Aluminium Company, says, “In windows, Aluwood Windows is still a nascent offering in India. These systems have combined the benefits of wood-naturalness to aesthetics of the environment and offer higher thermal insulation which prevents the transfer of heat. Besides this, since they are aluminium, they are lightweight, environment-friendly, stylish, durable, and 100% recyclable.”
Glass Wall Systems has constantly experimented with materials and design for its prestigious projects.
Technology & New Elements
Gone are the days when people put pen to paper to design engineering marvels. In the age of technology, people prefer modelling their buildings in various BIM tools and generating drawings from there. Dr Reddy says, “REVIT is fast becoming ubiquitous since it has various plugins that renders 3D image of the building. This way renders can be created for various façade options and the best one can be chosen without the need for a physical mock-up. Also the suite of energy simulation software like EnergyPlus, VisualDOE help in analysing and understanding the energy and daylight performance of a building even before the foundation is laid.”
Varghese says besides REVIT, 3D Max, Tekla, Lumion and CREO offer a view similar to that of a walkthrough.
While Shukla of KK Holding prefers to work with REVIT and Inventor to simulate complex design and shapes. The usage of enhanced software offers the fabricator complete clarity.
Technology is transforming with BIM (Building Information Modelling). Today, most façade systems are modelled in BIM and the 3-dimensional model is then incorporated within the BIM model of the entire building to check for interferences with other trades such as MEP, civil etc. “At the façade system design stage, we model the system in BIM and then produce prototypes with a 3D printer to check for interferences and or any other unforeseen issues in the mechanism. We also use thermal software such as Flixo in order to reduce the U-value by reducing the thermal bridges in a façade system. Additionally, we use Non-Linear Structural Analysis software to use iterative calculation methods to optimise sizes and thicknesses of façade with complex geometry,” says Keswani.
In terms of modules to simulate different times of day, there is a trend to develop sun-shading elements with controllable parameters so as to reduce the heat-gain at different times of the day in each season. Aluplex had design-engineered and installed the same a decade ago wherein motorised sun-shading louvre system was affixed to the façade.
These are energy efficient models that begin with sun path analysis for a year and design the extent of projection of horizontal and vertical shading elements to simulate with the analysis. “In an advanced model, the shading elements are movable and sensors are attached to simulate the movement as per the sun’s path for the day. The idea is to maximise the benefits of energy saving and provide comfort to people by eliminating sun radiations inside. This method can be used to bring more indirect light to inner core of the building by including light shelf inside the periphery,” says Varghese.
Occupants prefer façade materials that have functional benefits as much as visual appeal.
FunderMax too has developed a series of products called Max Lato which is the state-of-the-art shading system using high pressure laminates, says Dr Reddy. When designing shading of a building, there are few key aspects to be studied and assessed: Location, orientation of the building; sun path with respect to the building; and daylight performance.
The oft-missed parameter is the material of the slat which should not transmit thermal radiations. The wood-based HPL from FunderMax has far superior heat insulation properties and maintains the comfort of occupants. Key benefits can be realised in both thermal and visual comfort of the occupants not to mention the energy savings in the long run. Such options are available both in static and dynamic configurations.
There is a science behind windows and façade and one not to be taken lightly.