With Nagpur’s name included in list of ‘Smart Cities’ in India, the city needs to conform to its strict guidelines to become eligible for the grants under it. One of the conditions is to have many ‘green buildings‘ that are not only cost effective in long run but also helps owners to maintain good health, apart from helping to preserve environment by saving light and water.
Though the concept is fast catching up in India after developed countries, Nagpur is way behind, despite fact that its dry and hot weather is most ideal for such buildings that can reduce the outside temperature by as much 5-8%. Some like Hemant Sahasrabuddhe, project management consultant for civil engineering projects, are making efforts to apprise the citizens of a slew of benefits of living in a green building.
A penchant for environment conservation led him to pursue PhD in the field from Nagpur University. He also has a MTech degree from VNIT, MBA in human resources, besides being a law graduate.
In an interaction with media, he explains in detail about what green building is all about.
Q. How did you get into this field?
A. I worked with the Nagpur Municipal Corporation for over two decades and was active in the Integrated Road Development Programme (IRDP) with then commissioner T Chandrashekhar. It was only after I opted for voluntary retirement scheme (VRS) and joined a big upcoming project coming up near Mihan, with capacity to house 50,000 people, as vice president (planning) that I actually took interest in this field. Attending the Indian Green Building Congress in Hyderabad at the majestic building of Indian Green Building Council (IGBC) actually prompted me to work in this largely unexplored area.
Q. What is a green building?
A. The norms for certifying them are designed by US-based LEED Rating Council, which are followed globally. Known as ‘Leadership in Energy & Environmental Design (LEED)’, it’s a green building certification programme that recognizes best-in-class building strategies and practices. The buildings need to strictly follow its norms that enable them to earn points and win different levels of certification. However, countries have different demography and climactic conditions and, therefore, the norms are also tweaked as per local requirement. In India, IGBC frames the norms and awards certification like platinum, gold and silver. Broadly speaking, such buildings must have integrated lighting, improved comfort and air quality, and better sanitation at lowest cost and with less environmental impact.
Q. Any example of such building?
A. I don’t remember any in Nagpur, but if you visit IGBC headquarters in Hyderabad, you will feel the difference. That complex doesn’t have air-conditioners, and even ceiling fans are barely used even in the harshest summer. It doesn’t require lights in the day, and the requirements are a bare minimum due to its unique design.
Q. What is the difference between conventional and green building?
A. The green building would have soil layer intact, which is good for gardening purposes. It will have solar water heaters and even lighting should be based on it. Importantly, it should have A sewage treatment plant (STP) that can recycle the waste water, along with rain water harvesting. Even the showers and taps are designed in such a way that it should release minimum water, which is normally 6.5 litres/minute. Additionally, the lighting should be based on LED/CFL, while walls should be capable of reflecting heat and even overhead water tanks should be designed in such a way that inside water should remain at normal temperature. The roof tops should be design in such a way that it should absorb less heat from outside. In all, the green home should be able to reduce outside temperature by at least 5%-8%.
Q. Such buildings must be expensive?
A. They cost just 10% than normal ones, due to use of extra material. This is a good investment as within 2 to 5 years the costs are covered when one compares it with the long-term benefits. Even in health terms, there is a huge benefit. It also reduces power and water tariffs, and helps to save and preserve environment. The building’s life also increases due to use of green technology. The government should make it mandatory for builders to construct only green buildings, and offer them concessions in materials.
Q. Tell us about material used for green buildings.
A. The walls should be constructed with ‘Auto Caved Aerated (ACC) Blocks’ which are made up of dry ash and aluminium powder. These are not only lightweight, but also absorb 1/3rd heat as compared to a brick. Its size is also big, thus providing less joints even as it strengthens the structure. One ACC block is equivalent to four normal bricks. It even helps in fast erection of wall structures due to lightweight and bigger size, as less labour is required. Alternatively, there should be a gap between walls and windows for better insulation that helps to reduce temperature. Even the roof should be made up of specially designed ‘styrofoam sheets’ that reduce 20% outside heat. The use of ‘Low Volatile Organic Compound (VOC)’ paint along with ‘Low Emission Carpet’ tiles, which have low glazing properties, are also a must. The building should have south west projection and windows should be in shadow region of the sunlight. Use of localized material is encouraged in IGBC’s certification programmes.
Q. You talked about using STP and solar power.
A. For a flat scheme of 10 homes or more, they’re indeed feasible. STP’s modular units up to 50 cubic metres are available at 3-10 lakh. The recycled water is extremely useful for the agriculture and gardening purposes. Nowadays, innovations are made in solar power. In Chennai, prisms were used to direct solar light at home through special arrangement, which looks like normal light in daytime.
Is Bangalore listening?