With housing projects scaling new heights quite literally - on an average today, residential apartments are 15 stories high if not more - and with important cities like New Delhi falling in the seismically active risk zone, it is important to know if the skyscraper you are living in is actually earthquake resistant.
In India, super-tall structures are being built using the reinforced cement concrete, or RCC, design technique to ensure they withstand earthquake tremors. As part of this technique, concrete pillars with iron bars are inserted deep into the most stable part of the ground. The iron bars that emerge out of the surface are then interlocked with a thick slab of concrete called the raft. This piled-raft provides a solid base that can take on the entire load of the building. The piles at the bottom of the surface provide flexibility to the building to sway and still balance itself in the event of an earthquake.
Ani Ray, managing director at ACC India, said the design helps in passing the load on to the raft. This burden is then transferred on to the pile, thus ensuring balance.
In India, a National Building Code spells out the regulations that all agencies involved in construction have to follow. It serves as a model code, which, structural experts say, is its biggest loophole.
"These codes are just suggestions. They are not binding. People should follow them. But it is not law," said Dr Vinod Jain, managing director at Vintech Consultants.
Often, high-end skyscraper projects are backed by international experts which ensures that they strictly follow all norms to construct a structurally safe building. But poor compliance and lack of knowledge among local development authorities leaves enough room for average-sized apartment projects to cut corners.
"We are training masons, workers because in India, we don't have such qualified people. So there is an effort from NDMA (National Disaster Management Authority) to offer training at the ground level so that future buildings are earthquake-proof," said Professor Harsh Gupta, member at NDMA, adding that better implementation of existing rules is needed.
So how do we ensure that we are buying a structurally safe home?
"It will be very difficult for the buyers to find out if a building is safe or not. They (buyers) should insist from their developer a structural stability certificate to feel confident that yes, they are living in a safe home," Dr. Jain added.
Fire safety is another feature that customers should ensure is available in the project they pick. Fire-fighting equipment like extinguishers, fire hoses, sprinkler systems, fire alarms should be installed at every floor. A public address system is critical during emergencies.
Also, every apartment building with three or more floors must have a certificate of approval from the director of the local fire force or an authorised officer. It is imperative that these documents be checked once before purchasing the house.
Natural or manmade disasters don't come announced. In such cases, it is better to be prepared.