Dossiers en cours
2008 / 2009
dph participe la coredem
04 / 2010
There is a buzz about green buildings. But the question is: what does one mean by building green? And how does one design policies to make the green homes of our dreams?
Green is not about first building structures using lots of material and energy, and then fixing them so that they become a little more efficient. Building green is about optimizing on the local ecology, using local material as far as possible and, most importantly, building to cut the power, water and material requirements.
Take the glitzy airport building Delhi will soon get. Developers say it will come with a green tag. This is because the airport is investing in energy-efficient lighting, sewage disposal and rainwater harvesting. All these are important initiatives but the question remains: could the airport have been designed differently so that it used much less energy in the first place? For instance, the challenge before green airports today is to make them compact to reduce the time it takes from entering the building to entering the aircraft. This ‘frugal’ planning will make everything more efficient—take less building materials to build and less energy to cool and heat. But planners first think of building the biggest structures and then try sugarcoating them. I say this without even discussing the need for airports to give way to other modes of much more efficient transport like railways.
If one begins to think green in a locally appropriate way, one will realize that traditional architecture was green in many ways. Every part of India had its unique stamp of buildings. This is because creative and architectural diversity was built on biological diversity. So buildings in hot regions would ensure corridors directed the wind so that it naturally cooled the interiors. In wetter regions architects would build using the natural breeze and light. All in all, traditional architects knew how to optimize the use of elements.
Today, Indians have forgotten how to build for their environment. Instead, modern buildings are examples of monocultures—lifted from the building books of cold countries where glass facades are good to look at and appropriate for their climate. The same building in India is a nightmare; the glass traps the heat. The building cannot be naturally cooled because windows cannot be opened. It needs central air-conditioning and heating. In this situation, turning the building green means using very expensive glass to insulate better. Builders avoid this. So the only band-aid green measures left are to include a few token items like efficient lights and water-saving devices in the toilets.
Architects say God is in the details. In this case, the details are about both simplicity and diversity. In large parts of India, where the sun is both the source of light and heat, traditional architecture made use of a small but critical detail: the window shade. Modern facades are built without these shades because they don’t fit the image of the western building. Just raise your head and look at the glitzy building out there, you won’t find this simple but effective detail.
Clearly, the buildings of the green future have to be different. This will require setting the right policy so that practice can follow. The fact is even today we have no mandatory green standards for builders to follow. The National Building Code does not include energy, water or material efficiency standard. The only standard that exists is for energy—the Energy Conservation Building Code—and it is voluntary. The first and urgent step is to incorporate this voluntary energy code into the mandatory National Building Code. The second step is to ensure its implementation so that builders measure and reduce the energy usage of their construction.
But most importantly, the code must be developed so that it sets the mandatory benchmark for builders to follow—tough standards for energy usage for each square metre of built-up area. This will then allow architects and builders to do things differently. They can build for efficiency and cut costs rather than build for inefficiency and then spend money on making the building more efficient. This will bring back the knowledge and practice of building to maximize passive energy, natural light and wind, while keeping away the heat.
Simultaneously, the code needs to be expanded to include water and waste standards—to reduce water usage in toilets—and to ensure that institutions and large residential complexes recycle and reuse sewage. Similarly, these complexes must be provided space to compost kitchen waste. But priority should be segregating solid waste. Separate what can be composted or recycled and minimize what cannot be reused (like plastic).
This is only the beginning. Green buildings alone won’t make a city green. If green homes cannot be connected with public transport then the lives of the people living in them and the environment would still be brown and dirty.
This sheet is available in French: Immeubles verts : comment les repenser ?
Articles et dossiers
Sunita NARAIN, “Green buildings: how to redesign”, in Down To Earth, 15 April 2010