Project Description

This is a complex of 91 homes by a private developer, with near-autonomous state-of-the-art energy, water and recycling systems, including water recycling and conservation, decentralized waste-water bio-treatment, solar hot water, central thermal energy-conserving airconditioning and refrigeration, electrical load optimisation, low embodied energy materials including soil blocks, eco-friendly infrastructure development, trying to achieve a sense of the ‘housing of the future’.

Tzed homes crop 1

Building Details

Residential complex

New building project

20,000 m²


2 BHK and 3BHK Apartments, 4 BHK and 3 BHK Villas

76 apartment homes, 15 independent homes

Average 250 sqm m²

24,500 m²

20000 m²

4,000 m²

Became first IGBC Platinum Green Homes Project in India, certified AFTER commissioning!

INR 350 million

INR 14,285/m2



Project Team

Biodiversity Conservation India Limited (BCIL)


EMAS, Standard Construction, BCIL

SP&A (SHiFt)

Sanjay Prakash & Associates (SP&A), now Studio for Habitat Futures (SHiFt)

SHiFt (Studio for Habitat Futures) is a group of building technologists oriented towards design for the future. Not a future that is extrapolated from the past – with high consumption and high waste – but a future that is sufficient, regenerative, and efficient. The attitude is symbiotic rather than antibiotic, aiming for fulfillment rather than blind achievement. SHiFt is known for its innovative approaches to architecture and project management. SHiFt operates in the fields of energy-efficient architecture, eco-friendly design, and people's participation in planning. For over 30 years it has been working with passive and low energy architecture, hybrid air-conditioning, autonomous energy and water systems, earth construction, community-based design of common property, and computer-aided design. Its teams consist mainly of architects, engineers, and project managers with varying backgrounds. This multi-disciplinary mix helps it to remain innovative and efficient simultaneously. SHiFt was previously known as Sanjay Prakash & Associates (SP&A). Website: http://shift.org.in/

SP&A (SHiFt)

IAES (now McD BERL Pvt. Ltd.)

IAES (now McD BERL Pvt. Ltd.)

Lirio Lopez

In Antis (now Space Matrix) Associate Architects

Climate Analysis

Bengaluru enjoys a tropical moderate climate with separate wet and dry seasons. Bengaluru has a high altitude for its latitude, and that makes the climate moderate all through the year, though some heat waves can arrive in the summer (March-May). The coolest month is January and the hottest is April. Average temperatures vary between 15 °C and 35 °C through the year. Begaluru gets both the northeast and the southwest monsoons and September has the maximum rainfall. The summer heat is moderated by fairly frequent thunderstorms, which occasionally cause power outages and local flooding. Most of the rainfall occurs during late afternoon/evening or night and rain before noon is infrequent. The heaviest rainfall recorded in a day was 179 mm in October 1997.

Design Approach

• The built-up area was decided on the carrying capacity (water harvested) on the site. The total number of homes is 91 as against the 450 homes which any conventional campus would offer. • This meant that the homes would have to be built as high-end products with larger saleable area to ensure that the project was feasible for business. This in turn meant that the homes would be become high in energy consumption. • Hence, energy saving measures had to be incorporated into the design and operation of the campus. • The site informed the design in that that no tree, not even a palm tree, was cut, raised, transplanted, or altered (which meant respecting the original planting levels of all trees despite semi-basement type situations in the design) • The overall height was consciously taken to remain at about the tree top level, 15 m high, making for a convivial development with ease of handling fire safety.

• The building was designed incorporating passive design principles, ensuring ample daylight is available to homes. • East/west facades are well shaded and cross-ventilation is taken care of. • Sky gardens have been provided to enhance the micro-climate of the homes. • BCIL has built nearly two million square feet of residential homes in gated communities over the years, offering green solutions without making any compromise on urban comfort and convenience. • The designs have always been resource-sensitive and have given special attention to embodied energy of materials used. Most of the materials used have been sourced locally and most of them use very little energy at the source of production. • BCIL's eco-homes seek to address the need for water right from the commencement of a project to the post-occupancy needs of residents for healthy, continuous water supply. • In a city like Bangalore, this will mean that groundwater depletion will nearly stop, and we may find ourselves water-surplus with what we get from Cauvery.


Special Feature

• The building was designed incorporating passive design principles, ensuring ample daylight is available to homes. • During the day the total lighting load is likely to be near-zero in all seasons.

• There are no hard impermeable roads anywhere in the campus. • No new bore-wells were created. The existing ones are recharged through a network of 52 recharge wells. This must be one of the most intense ground water recharge systems in India. • Water is harvested, conserved and recycled with a unique network of shallow, open wells that supply all water needs of the campus, without the need for deep bore-wells that deplete groundwater resources. • Water-conscience meters keep members aware of usage of water. • A dual plumbing system is provided so that all sewage is recycled for using flushing and/or irrigation. • All grey waste water is treated and reused for gardens in a way that such water eventually percolates into the open wells and so completes the loop of use, treatment and reuse. • There is no sewerage connection for this campus.

• Use of passive solar architecture in the design of buildings. • East/west facades are well shaded and cross-ventilation is taken care of. • Sky gardens have been provided to enhance the micro-climate and to cool down the homes. • An appropriate level of fenestration, insulation, colour and shading have been employed according to orientation to suit the local climate.

• Reduction of food miles through Zero food Miles programme. City farming in cement bags and containers use up spaces like terraces and sky gardens too for growing vegetables. About 7 tonnes of vegetables can be grown annually. • Embedded renewable energy systems translates into the campus consuming only 60 per cent of energy demanded normally. Residents pay 30 per cent less on power and 20 per cent less on monthly maintenance. • Design of energy efficient refrigerator. It works on about 1.8 to 2 units less energy consumed per day against a regular refrigerator of similar size. This amounts to a financial saving of over $ 120-215 a year saved on energy bills in every refrigerator depending on which state you calculate for [$ 0.125 per unit in Karnataka; $ 0.2125 per unit in Gujarat or Kerala or AP]. • T-Zed water heating comes free for a life time, since it is solar powered as against the regular geyser whose power costs you $ 10 minimum per month. • Use of home automation systems for energy efficiency. • 20,000 tonnes of CO2 capital savings could generate approx. $240,000 as saleable carbon credits. This is through the sustainable design introduced in handling of o Basement structure providing great lighting and ventilation in the parking areas o Basement retaining walls use dry masonry instead of concrete o Independent home superstructure is load bearing o External earth walls o Internal flyash containing block walls o Mortar for external walls without river sand o Mortar for internal walls without river sand o Plaster internal walls reduced o Plaster external walls nearly eliminated o Internal surface finishes with low emissions o External surface finishes with low emissions o Internal flooring without ceramics o External corridor flooring without ceramics o Connecting bridge without ceramics o Connecting bridge deck without ceramics o Swimming pool structure SSM walls with raft o Swimming pool cladding in sandstone, not ceramics o Club roofs in stone, bamboo and autoclaved aerated fly ash blocks o Floor and wall tiling in washrooms avoids all ceramics o Use of Non-forest timber such as rubber wood for door and window shutters • 1,500 tonnes of CO2 operational savings could generate approx. $18,000 annually through o Lighting and ventilation o Air-conditioning o Refrigeration o Water heating reduction o Water consumption reduction o Solid waste management o Organic waste handling

• Bio-digester for efficient solid waste management. • Landscaping using eco-sensitive design practices involving only indigenous species. • This is the first residential campus in India which is acquiring certification for carbon credits and sequestration for not only the campus but also for its residents. Capital savings of approx 20,000 tonnes of Carbon emissions. Operational savings of approx 1500 tonnes of Carbon emissions. • Design of India’s first centrally air-conditioned (with no CFC and HCFC) residential campus to ensure good Indoor Air Quality with an environment friendly AC system. It has a Thermal storage tank which feeds the plant when optimum temperature is reached. • 6 inches of topsoil that got removed during construction was reused for gardens within T-Zed. • Bio-diesel is used in gen-sets ensuring use of renewable alternates.

• When people live in such communities that are sustainably developed, they realize that they are not buying a house, but are buying into a way of life that brings them a higher value in life. Such communities have awakened members to the new sensitivities of rational views of water and energy without having to compromise on comfort and convenience. • Home-owners in the community have voluntarily created an eco-cell for ensuring sustainable parameters of building management are pursued and implemented with vigor and effectiveness. (http://ecobcil.com/content/client-testimonials). • They understand, appreciate and make their own the pioneering features of green buildings built by BCIL. • The 91 T-Zed families have been involved in laying down certain practices within the campus. A community library has been started where residents voluntarily keep their books which are available to their neighbors. The residents have been advised in planting indigenous species in their backyards and sky gardens which they are more than happy to adopt to keep alive the spirit of the project. Waste segregation happens at individual home level thereby enabling the campus to maintain its waste management programme. • Critical Instruments: o A: Regulatory Instruments • A.1: Regulations • A.2: Standards • A.3: Guidelines o At the time of building T-Zed, there were no benefits, incentives, guidelines that help green builders in India. • B: Economic Instruments o B.1: Tax and Charges o B.2: Subsidies o B.3: Private financial mechanisms for infrastructure development • Private banks have funded our customers through loans. • C: Social Instruments o C.1: Participation o C.2: Awareness: • BCIL has played a major role in creating sensitivity amongst the T-Zed residents by educating them about the features of every home. T-Zed Dossier and other such publications have been released at various stages of the project and circulated amongst the employees and the residents. A user manual is in the process of being documented to aid in the management of the facility. o C.3: Partnership o C.4: Empowerment • The residents have been slowly initiated to take on the management of the campus. They have independently started the ZEDRA (Zed Residents Association) which monitors and manages the facility as per the guidelines set by the developer o C.5: Information and Communication o C.6: Self-Regulation o C.7: Organizational Arrangement o C.8: Capacity Building

Building Material

• T-Zed has the largest utilization of Soil stabilized blocks in the residential sector. These are unburnt bricks stabilized using locally available red soil, 3-7% cement, some granite dust and a little water. This gets pressed in a hydraulic form and gets cured under sunlight for a week. • Laterite blocks (blocks cut out of laterite stones) and concrete blocks have also been used for external walls. • Granite dust was used instead of precious river sand for mortar. • Internal walls use 10 cm concrete blocks.

• Largest possible use of rubber wood from trees which are sustainably harvested. Doors use this wood instead of the usual MDF boards.

• A combination of wooden and natural stone flooring. • External flooring has rough hewn natural stone instead of ceramic tiles.

• RCC/filler slab for the roof over the restaurant instead of conventional RC slab, using recycled railway sleeper bits as the filler. The vaulted restaurant roof has been erected by traditional earth scaffolding. Reclaimed wooden fillers allowed savings in material consumption.

Energy systems

• Though interior lighting is the choice of the resident, CFL-based loads have been provided and informed to the users so that they conserve the energy demanded for lighting.

• A CFL/LED hybrid was developed for street lights. LED technology had not fully caught on at the time of commissioning especially in the residential sector. Since LEDs provide direct lighting they could not be used alone in the luminaries, so the possibility of combining CFL and LED technology in outdoor lighting was explored. The CFLs switch off late at night and only LEDs remain turned on when the light levels required are low.

• Automated fans save energy. • Solar washroom ventilation and remote controlled electric switches.

• Larger home sizes at high end meant that the homes needed to be air-conditioned. Conventional practice would mean that every home would be fitted with A/C units which are high-energy guzzlers employing ozone depleting refrigerants. We saw in this situation a huge opportunity to centralize the air-conditioning system and use ammonia (non-ODS) as the refrigerant. Cooling of air was designed to be done in two levels – primary level of pre-cooling the air by means of cooling towers and secondary level of cooling by chilled water. The A/Cs are fresh-air based which are controlled at the unit level by means of a lever. But the challenge is that the efficiency of the centralized system is ensured when at least 60% of the units are in use. • Design of a central energy efficient refrigerator. It works on about 1.8 to 2 units less energy consumed per day against a regular refrigerator of similar size.

• Power meters keep members aware of usage of energy. • Use of home automation system for energy efficiency. Home automation – the security alarm, lighting, fans and ACs are controlled from the residents cell-phone by merely sending a message to the main control panel.

• Built-in solar hot water systems help save a tremendous amount of energy. T-Zed water heating comes free for a life time, since it is solar powered as against the regular geyser.

Lessons Learned

Design team • Despite all the care that one may take in providing features and value engineering them so as to remain cost neutral, there is no substitute for holding continual workshops with residents and buyers in order to make them aware of what they are buying into. • That mainstreaming the use of SSB in such a large context was possible. • That enabling of community participation could yield such positive results. Marketing • While customers liked green ideas, it took them a long time to cross over from living a consumerist life to a greener life. We had to strategize not to make it difficult for them. This process has evolved over the years and we are these days more conscious of making it painless for the customer to lead a green life. • The first impact which impresses customers has been the fact that green homes are available at almost the same initial cost as any other conventional building. On top of this, they also get to save money through energy efficient systems within site. Developer • Learned of carbon credits after commencement of the project and it has taken a length of time to understand the mechanisms and see how it can benefit the end user namely members of T-Zed. • Our biggest lesson was the fact that it is possible to be water-positive in Bangalore.