Excerpt from the conversation originally published in WFM Magazine, March 2019
Q1 – Glass has become the chosen medium for facades – both building fenestrations and cladding – and as a material for load-bearing elements such as roofs and floors. Is it good or bad considering the Indian weather conditions? What is your view on growing demand for glass in niche and low-rise applications?
A1 – Glass is a default material in any building. The quantum of glass used in a design is dependent on various tangible and intangible reasons. Accounting for Local weather conditions has become one of the tangibles + measurable components in façade design. So its no longer a question “if” glass is going to be used, it is discussion on “how”.
Q2 – Throw some light on choice of glass for fenestration?
A2 – Again, this is totally dependent on the utility / intention / scale / cost / application. From clear glass to coloured. From float to laminate. Using glass independently or in combination with other techniques / materials.
Q3 – Please brief on limitations of having complete glass walls on buildings considering Indian climatic conditions? Would you combine glass with other materials for better performance and why?
A3 – “Indian Climatic Conditions” are extremely variable. However, we recommend using complete glass walls with caution. Caution for orientation, caution of choice of glass, Caution for Vision clarity, Provision of shading devices (Louvers/Screens/shelves). This is further enhanced by the building design / massing.
Q4- Can glass as a façade material be matched to the need for carbon-neutral buildings with eco-friendly features?
A4 – As mentioned, glass alone cannot address all concerns. To achieve Net-Zero, it will always be used other materials. Each with its on methodologies and intricacies to achieve Net-Zero. As mentioned earlier, application of glass is irreplaceable. The question arises, on the intelligence of application. This is where a close communication between the manufacturing world and the design fraternity is critical.
Q5 – Natural light is beneficial and is necessary, the heat energy inside the building has to be managed especially during summer. What are the factors affecting solar heat gain? Brief on light and heat management in buildings with glass facades.
A5 – Elaborating on the above point of communication between the manufacturing and design; materials like SAGE from Saint-Gobain, enhance the possibilities of design and orientation. This is not necessarily an endorsement of a product but the idea that there are products available that push the boundary on conventional design principals. Achieving clarity and yet addressing heat percolation. Cutting glare yet ensuring vision.
Q6 – Please tell us about the performance of glass in acoustic insulation?
A6 – Acoustic Insulation the principals are slightly different from heat insulation. The progression for acoustic should be 1st to increase the thickness of the glass than to jump to DGU principals. Also, in the case of DGU, one should remember to create a differential in thickness. Depending on the methodology of glass (thickness/DGU/lamination) the decrease in Db can be attained.
Q7 – What is the awareness level of consumers on the terms such as solar shading, double-skin facades and ventilated facades?
A7 – The onus of educating the consumers / clients lies both on the architect and the industry. Every client is willing to understand the importance of devices, techniques that would improve the quality/life/comfort of occupants of the building. Needless to say, cost and aesthetic are also strong drivers in decision making.
Q8 – In India, does the market has the agility and expertise to provide products and systems to meet even the most exacting of specifications and norms? What is your take on this?
A8 – Indian construction industry works at 1/5th to 1/7th of cost compared to Middle east / Europe / US or other organised markets, where the protocols are also more stringent. There is a catch 22. The problem is that while the clients are not willing to pay for the specialised expertise, there is an expectation of stringent delivery. Since, the delivery is non-exacting, an aura of negativity gets created.