Though high-performing building insulations are now available in almost all major cities of India, but few building owners know how, when and where to use them. However, with growing awareness about energy efficiency measures, it is expected that high performing insulation technology will penetrate more in India's building industry
Biswajit Roy
Global warming has been acknowledged as the common concern of mankind by all countries during the Paris Climate Change Summit in 2016. Arresting the rise of the global average temperature well below 2oC above pre-industrial level, has been jointly decided. Then, in the month of June 2016, India witnessed scorching summer months when the maximum recorded temperature in places such as Rajasthan crossed the 50oC mark - the highest in the last 60 years. In various parts of the world, the average temperatures recorded were above normal and oceans became warmer than usual. People were surprised to observe these rapid changes in their environment.
For countries like India, it is a question of fast development and protecting the environment at the same time. We all know that buildings are one of the major reasons for energy consumption or GHG emission. To make a building energy-efficient, one of the best ways is to insulate it. Though we have been using insulation for the centralized HVAC or refrigerant lines for a long time, insulation of the building envelope stills needs more attention, especially in the residential sector. Fortunately, high-performing building insulations are now available in almost all major cities of India, but few building owners know how, when and where to use them.
Fiberglass wool is one such insulation material that can be applied in almost all the important envelope applications. Some of the areas include the following:
Underdeck insulation: Fiberglass wool boards or blankets can be installed in the underside of the RCC roof slab with gypsum or plaster ceiling system. The insulation should be vapour-barrier laminated and should be of minimum 50 mm thickness for better thermal resistance. It helps to reduce the effect of high external temperature inside the building by resisting heat flow across the roof from outside to inside. If air-conditioned, underdeck insulation helps to reduce AC's energy consumption by reducing the total heat load of the building. Insulation units need to be fixed to the RCC with the help of polyamide-based insulation fasteners.
For residential units, where plaster board ceiling may not be an option, underdeck insulation rigid fiberglass wool boards with flat and paintable fiberglass cloth laminates can be applied over a pre-installed metal frame system.
Wall insulation: Fiberglass wool insulation boards can be applied between two masonry walls erected parallelly. This application is only possible during construction of the building. Normally, wall ties are applied between the two walls to keep them together and these wall ties also provide support to the insulation boards. In some of such applications, fiberglass wool blankets are also used, where the wall leaves are constructed one at a time and not simultaneously. Once again, polyamide-based insulation fasteners may be useful to install the boards with minimum thermal bridges. If a cavity wall construction is not possible, insulation as a wall liner can be applied with the help of gypsum boards and metal frame.
Most of the commercial buildings have a tall façade system at the external wall. Façade insulation application requires tissue laminated fiberglass wool boards. The insulation boards can be applied on the wall independent to the façade system, or they can be mounted along with a glass-metal box that is assembled with the insulation inside before installation on vertical rails fixed to the external wall. For the insulated glass facades (opaque), normally, the colour of the tissue is black so that the colour of the insulation (which is usually yellow) is not visible. Sometimes, for green coloured glass, green tissues are laminated on the fiberglass wool boards.
Advantages of Fiberglass Wool: Fiberglass wool is a safe product. It is non-combustible, least ignitable and free from smoke and toxic gases. Made from pure glass fibers, well distributed and bonded with phenolic resin or other type of binders, this high-performing insulation material is one of the most time-tested and proven materials. Available in various forms and sizes with ample lamination options, fiberglass wool can meet the basic need of thermal as well as acoustic design requirement of buildings. Moreover, the products are completely safe from environmental and health aspects and approved by green product certification bodies like Singapore Green Building Council and TERI.
High-performing fiberglass wool insulation has a history of more than 80 years and has evolved over this period since its invention in 1930. It is now one of the popular and used insulation material for the building industry in USA, Europe, Japan, South Africa, China, Brazil and lot of other developed and fast developing countries. In India, till now, mainly commercial buildings and some big-size residential projects are using insulation products. In the near future, with growing awareness on energy efficiency measures, it is expected that high performing insulation technology will penetrate more in the Indian building industry.
