India does not have any mandatory specifications to be adhered to in the use of glass - something that is present even in a country like Bangladesh.
Given the fact that many Indian cities are in seismic zones IV and V, it is imperative that the glass used in buildings have in-built safety features in them, explains architect Deepak Gehlawt, who heads the Confederation of Construction Products and Services, which is working to evolve standards for the glass industry and is also holding architects workshops to sensitise the profession to the right glass to be used.
Safety in glass comes from the fact that the glass used should crumble and not break in shards in a disaster. For this the glass used in buildings should either be toughened or laminated.
The cost of using toughened glass as opposed to ordinary glass in a building works out to an additional cost of Rs 30-40 per sq ft more than ordinary glass. In an average residential apartment that works out to about Rs 50,000 to the overall cost of construction. In addition, the users can do away with grills that could probably save the user the money anyway. In addition, it also protects the building against sound and ultra-violet radiation.
Explains Narain, Today buildings are becoming taller and the glass span used is bigger too. This increases the risk of the damage caused by glass in case of an accident. Increasingly, developers are using more glass than traditionally to project a more international look.
Today in most commercial buildings the percentage of glass used is 25-30% or higher. Steel, concrete and glass have emerged as the three leading building materials.
Not that accidents have not happened. In a five-star hotel in Mumbai a large glass piece fell about two years ago - with no damage to life. Large developer groups such as the DLF and Hiranandani too have have had glass falling off. However, no dramatic accident has been reported so far in terms of damage to human life.
Most commercial buildings today are safe, glasswise, says Narain. However, he maintains that almost all residential buildings are unsafe.
No study has been made into schools and hospitals.
But with increasing quantities of glass being used in them, the issue of safety is being raised by users. In 100% of the cases that we have interacted with individuals, they have opted to put in safety glass despite the additional cost, says Narain. In which case, it is the basic lack of awareness that prevents the consumers from demanding safety glass in their buildings.
From the cost perspective too developers should not find it difficult to recover cost. Glass buildings today fetch twice the rental values compared to non-glass buildings. Ordinary glass contributes to 2-3% of the construction cost while safety glass contributes to 5-6% of the building cost. Therefore it is a recoverable cost.
Glass today poses a major hazard because unlike earlier designs, glass is now put on the exterior. This means that there are few building features that can break the fall of the glass. This poses a hazard to users within the building and those on the street as well, explains architect Vidur Bhardwaj.
Professionals complain that not only are there no mandatory safety regulations in India, even recommendatory codes in the National Building Code 2005 are not stringent enough.
However, organisations such as Glass companies as well as industry organisations like CCPS are banking on a sensitisation campaign for developers, professionals and consumers to drive a demand for safety glass.
With building after building in Mumbai falling and retail malls, commercial and residential buildings systematically using more glass for construction, user sensitivity may well be the first step to safer cities.