TERI advises architects, builders, developers, individual home-builders and organisations to evaluate the ‘health of a building’ with nationally acceptable green paradigms. The rating system is based on accepted energy and environmental principles that strike a balance between established practices and emerging concepts.
“We recommend location-specific alternative construction methodologies for going green in high-rises where modular and straightforward structural designs can bring down cement, steel and concrete consumption by nearly 25 per cent,” says Minni Sastry, Fellow & Area Convenor, Centre for Research on Sustainable Building Science, TERI-South Regional Centre. She is one of the green consultants involved in the GRIHA Building Certification taken up by the institute.
The conference, organised in the wake of the recent government policy on Smart Cities, brought together eminent scientists, research professionals, academicians, practitioners and building industry stakeholders, enabling the sharing of best practices and latest developments on sustainable habitats. It assumes significance as India is expected to become the third largest construction market in the world by 2025. However, the green building footprint is just about three per cent of the current building stock of 25 billion sq. ft, and this is expected to reach 100 billion sq. ft by 2030.
Minni Sastry answered a few questions for The Hindu-Property Plus
How do you see this conference in a perspective?
Increase in urbanisation and economic growth has resulted in increase of consumption of natural resources per capita. Higher incomes have given rise to higher standards of living and a boom to the real estate market in India. For example, Bengaluru has seen the development of lots of SEZs, IT parks and residential units.
When a large project is planned and implemented, there are larger environmental issues which need to be assessed and their effects that impact the built environment, as these developments bring in complex changes to ecology, natural resources and to the environment. For example, water as a resource is scarce and there is a huge gap between demand and supply, especially in new residential developments which have come up on the outskirts of Bengaluru.
The water demand is met by private tankers, due to shortage of water supply and in many cases, because the developments have occurred in areas where there is no BWSSB connection. Such a practice, from sustainability perspective, is a disaster.
To meet the water demand of the SEZ projects and residential projects, private tankers take ground water from neighbouring villages, and in return send solid waste from the city to neighbouring villages, with the notion of keeping the city clean. Also, the building material demand for the real estate industry is met by extensive granite quarrying, which is causing disappearance of hillocks in the city outskirts.
Such practices, if continued, surely will have devastating impacts on the ecology. The 6th GRIHA Conference in Bangalore by TERI had engaged with key stakeholders and deliberations to share solutions for accelerating and mainstreaming sustainability in the built environment. According to Jairaj, the right regulations and policies have to be in place. The Urban Development Department of the State Government needs to adopt GRIHA for New Construction and GRIHA for Large Developments (LD) for reducing the impacts due to built environment.
What is the GRIHA criteria?
One of the most important GRIHA LD criteria is to find out the carrying capacity of the land, for its ability to absorb population growth without considerable degradation or damage, and this is based upon water availability and available green cover per-capita.
The determining factors include:
1. Water – Quantum of municipal supply and other sustainable sources.
2. Green cover – Total per capita available/made available on site.
There is a need to integrate minimum mandatory regulations in the building bye laws of the municipality, in order to achieve the minimum sustainability principles in all building related developments. TERI has carried out an analysis on sustainable features that are cost effective and are a must for every new development. These can be summarised as:
Site-level sustainable features: Waste water treatment & reuse, rainwater harvesting, solid waste segregation & treatment, use of native landscape species, pervious pavements, use of local materials, renewable energy-based outdoor lighting.
Building-level features: Solar passive architectural design principles including natural ventilation and natural lighting, water-efficient fixtures, solar water heating systems and efficient indoor lighting.
Architects perceive that if they have adopted sustainable architecture principles, rating systems are not required.
My response to this in simple terms is: can we assess the efficiency of a car without knowing or calculating its mileage? When we buy electrical equipment, we look for the ISI mark which gives assurance on safety and quality of the equipment.
Buildings are also product of design. There are many architects in India who can design buildings very efficiently. But at the same time, there are an equal number of developers & architects who may claim to design and build a sustainable building. To avoid false concepts and claims, it is important that buyers make an informed decision, and demand a certified building.
GRIHA has many variants. SVA GRIHA certification is available for 100 sq.m to 2,499 sq. m of built-up area. GRIHA for New Construction Certification is available for 2,500 sq.m to 1,50,000 sq.m and GRIHA LD is available for site areas more than 50 hectares or built-up area more than 1,50,000 sq.m.
Through GRIHA (Green Rating for Integrated Habitat Assessment), projects are assessed for their greenness through quantifications and continuous monitoring. There are benchmarks provided for energy and water consumption, against which the building is assessed, and these benchmarks vary because of climate, building typology and schedule of the buildings.
Some examples we come across are:
* The architect claims to provide light naturally by design of north skylights. Rating systems such as GRIHA help in analysing the quality of light made available inside the building without causing overheating and glare.
* Architect claims to design a green building and has designed a naturally ventilated building along with use of stabilised earth blocks. Rating systems like GRIHA assess the thermal performance of the building on an hourly basis throughout the year and hence help the designer community take a much more informed decision on the selection of building materials.
