Depending upon the architectural design of the building, the external cladding can play a significant role in the structural design of a building. External factors such as high winds and rains play a crucial role in the selection of materials for façades and their design. Also, high-rise buildings have a stringent regulatory requirements while designing the façades. Facades could be designed purely as aesthetic elements that are clad superficially on the buildings, or as a full-blown structural component integrated with the building structure such as the 750-seater auditorium that we designed for the Symbiosis University of Applied Sciences, in Indore.
What are the key factors to be considered while designing and selecting materials for cladding?
Cladding is often prefabricated in panels that are attached to the structural frame of the building. Cladding systems may include additional components such as windows, doors, gutters, roof lights, vents, etc. The nature of cladding selected for a particular building may depend on the internal and external conditions, durability, weather, site context, budget, maintenance, structural requirement, location sensitivity, fire safety, material availability, detailing ability to achieve water tightness, cleaning ability, and aesthetic quotient. High-quality, well-designed, properly installed cladding can help maximize thermal performance, minimise air leakage and optimise natural daylighting. This can help reduce the mechanical and electrical burden on a building.
What are the best-suited products considering the Indian climatic conditions? India has a varied climate depending on the geography, from warm and humid to cold and dry. Therefore, the best-suited products could vary from place to place. Terracotta cladding is great for Indian weather conditions. The tiles modulate heat according to climate, their look imparts warmth, and they are eco-friendly and a smart alternative to exposed brick masonry. Terracotta cladding is made of natural clay and comes with qualities like high durability, good UV resistance, acoustic resistance and heat insulation.
What is the role of Terracotta cladding in controlling the internal environment and acoustics in a building? The cladding system can control the internal environment of the building such as controlling light penetrating into the building, controlling the radiation and conduction of heat from the sun, etc. This is due to the solar gain through the glass panels. The internal temperature can be controlled in three ways. The first is by using a deeply recessed window in conjunction with external vertical fins. Secondly, by using non-transparent external louvers and thirdly by using a special solar control glass.
How can it provide better thermal insulation, at the same time support effective ventilation?
The cladding system should include thermal properties by controlling the radiation and conduction of heat. Thermal insulation is achieved with the use of appropriate material and detailing, and effective insulation is achieved through engineered integration of the ventilation system into the cladding. Insulation on the inside of external walls is the best solution if insulation from outside is not an option. Even older buildings with listed facades or those worth preserving often have low thermal insulation, which can be improved by more than 60 per cent by internal insulation.
Installation is also comparatively cost-effective because no scaffolding is required for the building and it can be applied on a room-by-room basis. Maximum heat can escape through external walls if virtually unchecked. Many buildings are designed with double-skin masonry for visual or structural reasons or as protection against extreme weather conditions. The cavity is given an insulating layer so that the cold air between the facing wall and the lining wall does not then cool the internal skin.