Mumbai, Sep 16 (TNN): Mumbai has the country's maximum number of environment-friendly buildings under construction, a survey has shown. The city has 60% more green building projects compared to Delhi and Bangalore, which are second and third on a list released by the Indian Green Building Council (IGBC). The list has six cities, including Pune, Hyderabad and Chennai.

Mumbai has 319 registered projects that fall in the green building category and are spread over 229 million square feet, according to the IGBC. Delhi is second on the list with 199 projects, followed by Bangalore with 198 and Pune with 197.

The IGBC report says India with more than 2,111 registered green building projects covering 1.54 billion square feet is among the top five countries on the world green map.

A green building is one that uses less water, improves energy efficiency, conserves natural resources, generates less waste and provides healthier spaces for occupants as compared to a conventional building. "These are judged on the basis of material used, sites chosen, ventilation and use of lights, among other things," said a member of the Confederation of Indian Industries (CII).

Constructing green buildings is costlier. "Earlier, it was 15-18% more expensive than a regular building. Now, the cost has come down to 3-5%," said M Anand, principal councillor, CII. "A green building ought to use minimum quantity of glass. We insist on only 7-8% of glass use. Also, builders are asked to go for high-performance glass that won't reflect much heat."