When we look at different kinds of buildings, we may have very different reactions to them. Some are tall and imposing, with massive arched doorways and towering spires. Others are welcoming, perhaps with a large porch or wide windows. How these building entrances look is no accident. Someone designed them with a lot of attention, especially the facade, as it forms the first impression of the structure. When an architect designs a facade, they consider many elements. What will the entrance look like? What type of building material, like stone, wood frame, or brick, will be used? They must also consider fenestration or the placement and proportions of windows.
Throughout history, architectural styles have changed, and they continue to change today. Rohit Suraj, founder of Hyderabad-based firm Urban Zen, has no formal training in the field, but has been successful in the curation of many office projects and has won recognition for them. He shares his insights regarding the core challenges in facade installation and how the climatic condition affects the selection of facades; he further throws light on the concept of green facades.
What are the core challenges in facade installation in high rise buildings?
Facades are a reflection of a building inside out and outside in. The need to integrate this approach in design is more pertinent now than ever before, given the evolving role of skin or envelope surrounding the built mass – be it protection from external elements, maintenance of ambient internal temperature and ventilation and natural light while at the same time ensuring visibility from inside. In high rise buildings particularly maintenance and wind loads are key issues to stability and long term viability.
How does the climatic condition affect the selection of facades?
To maintain a comfortable environment inside the building, the façade must be climate responsive. Hence, extensive insulating properties should be incorporated in the façade to allow sufficient solar heat and natural ventilation. The improved insulation will, therefore, influence the interior of the structure. Climate studies are integral to the design of facades that are relevant during different seasons in the year.
What are the benefits of using a non-bearing, rear-ventilated facade?
With exemplary insulating properties, thermal insulation reduces the exchange of heat between the exterior and interior of a building. In summers, hot air vaporizes through the rear ventilation and establishes optimal temperature balance. It also reduces noise and provides sound insulation.
What are the factors to be considered to ensure the facade provides the required dose of heat and sound insulation?
Façade plays the role of an active skin – selectively allowing light but not radiation, ventilation but not heat and visual comfort but not glare. Smart building technologies now integrate the façade response to the internal lighting and heating conditions. On a warm day on an office building, for example, the shading devices on the façade tilt their direction to avoid direct sunlight entering the building glazing.
At the same time, the internal temperature auto-adjusts to ensure a room temperature of 23-25 degrees, and the lighting inside is brightened to compensate for the reduction in natural light. That said, there is a fine balance to be achieved between the investment and operational cost-effectiveness of such cutting-edge technology vs. sustainable long-term benefits of the same in every project. Truly successful facades do far more than merely projecting an iconic image; they play a vital role in driving or transforming building performance.
The Indian skyline has a mix of concrete high rises and ones with glass facades standing side by side, in this scenario; does the factor of reflectivity have any detrimental effect on the adjoining building? How can it be minimised?
The façade combines the aspect of appearance and performance in a building system. For a clear vision of the built-scape, it is necessary to minimize the glare of the glass buildings standing tall next to the concrete establishment. The other alternatives can be definite finishes on the façade or introduction of shading devices such as balconies, louvers.
What is the concept of green facades? How different is it from the regular facades?
The concept of green facades is essentially the process of designing vegetation on the face of the façade either horizontal or vertical. It involves a mechanism of budding climbers onto the surface of the façade or of it being sustained by an individual structure. The foliage of the creepers can be effectively used for shade and providing a cooler microclimate around the building. The approach of considering green façade is sustainable as it provides improved air quality and a living landscape.
When it comes to facade design at what stage of the building construction should it be brought into focus?
For a building to be functional, the open floor plan should coordinate with the façade system. Thus, it should be incorporated at a very early stage of construction. Considering the evolution of a design throughout, the façade also advances. Hence, the fusion of all the elements in a structure will need to be in harmony leading towards the final product.
How can glass facades be used as an element of aesthetics in the overall design scheme?
Glass, in its true form, has considerable elasticity which makes it a good building material for facades. There’s no evidence that glass deteriorates over time under stress. With its phenomenal aesthetic properties, it is also known to withstand the harshest of weather conditions. Also, enhancing its advantages, it is available in the market in so many different types- Tinted, Shatterproof, Toughened -being a few of many. In addition, glass is also used to make materials like GFRC (Glass Fiber Reinforced Concrete) which is moldable and has an excellent environment performance (GFRC is a fire-rated material with class 'O' rating, does not corrode and is safe to handle, has acoustic properties, weather-resistant) and is very quick in its erection on-site, saving both time and cost.
What steps need to be taken to ensure the facade is well maintained? When does a facade have to be renovated?
Facades are in direct contact with the external environment which makes it prone to dirt, dust and rain. Hence, the façade access system and cleaning system have to be planned for a building to be operational. Regular inspection and maintenance are necessary to identify the issues in the facades which lead to replacement or service. Early detection of defects will reduce the maintenance cost and would enhance the appearance of the building.