Annexure X- Green Building Provisions

1. Water Conservation and Management- Bye laws 10.2 (1)

The use of water conserving fixtures, landscaping, rain water harvesting, aquifer recharging and waste-water recycling need to be given due consideration as follows-

  1. Rain Water Harvesting from roof and non-roof areas (by Recharge) Design rainwater harvesting system to capture at least ‘peak-month rainfall’ runoff volume from roof and non-roof areas.
  2. Low Water Consumption Plumbing Fixtures Use water efficient plumbing fixtures (as applicable) whose flow rates meet the baseline criteria in aggregate. The total annual water consumption of the building should not exceed the total base case water consumption computed. The baseline criteria are as below:


  1. LPF: Litre per flush
  2. 2. Reporting pressure for these fixtures shall be at 3 bar.
  3. 3.Full Time Equivalent (FTE) represents a regular building occupant who spends 8 hours per day in the building. Part-time or overtime occupants have FTE values based on their hours per day divided by 8.
  4. Plumbing fixtures certified by IGBC under Green Product Certification Programme can be used by the project to show compliance, as and when certified fixtures are available As per MoEF&CC guidelines, water reduction can be achieved up to 36% using water conserving fittings with sensors, auto valves, pressure reducing device wherever possible which can result in significant reduction in water consumption.

i. Water closets (WCs):

  • Conventional toilets use 9 litres of water per flush. Low flush toilets are available with a flow rate of 6.0 litres and 3.0 litres of water per flush.
  • Dual flush adapters can be used for standard flushing for solid waste and a modified small flush for liquid waste
  • Flush valves with 20-25 mm inlets can be used for restricting the water flow

ii. WC faucets, wash basin taps, and kitchen taps:

  • Faucets and taps can have flow rates upto 25 litre/min. The flow rate can be reduced without compromising on the water pressure by having restrictors, pressure inhibitors and aerators. Auto control valves can further help in reducing wastage.
  • Pressure reducing device: Use of aerators can result in flow rates as low as 2 litre/min, which is adequate for hand washing purpose.
  • Auto control valves: Installation of magic eye solenoid valve (self-operating valve) can result in water savings. The sensor taps have automatic on and off flow control. It functions with parameters such as distance and timing.

iii. Urinals:

  • The conventional urinals use water at a rate of 7.5-11 litres per flush.
  • Low flush urinals use only 2 litre/flush.
  • Use of electronic flushing system or magic eye sensor can further reduce the flow of water to 0.4 litres per flush.
  • Waterless urinals use no water.

iv. Shower heads:

  • Conventional showerheads can deliver water at flow rates above 25litres/min.
  • A perfectly pleasant shower can however, be obtained with flow rates well below 10 litres/min.
  • Shower heads fitted with aerators and pressure regulators can reduce flow rates as low as 4.5litrs/min and their use will show a significant saving.

c. Waste Water Recycle and Reuse

i. Waste Water Treatment

  1. Design an on-site treatment system to handle 100% of waste water generated in the building, to the quality standards suitable for reuse, as prescribed by Central (or) State Pollution Control Board, as applicable.

ii. Wastewater Reuse

Use treated wastewater for at least 25% of the total water required for landscaping, flushing, and cooling tower make-up water (if the project uses watercooled chillers).The treated wastewater could be used for landscaping, flushing and air conditioning.

  1. Notes:
  2. Waste water here refers to both grey and black water
  3. Waste water can be treated in-situ and reused in-situ
  4. In case the local authorities insist the project to divert waste water to a centralized/ common waste water treatment plant, then the project can show compliance, by reusing treated wastewater from the centralized/ common/ any other wastewater treatment plant
  5. Treated waste water from other sites/ local authorities through permanent piped connections or other means can also be considered to show compliance
  6. Captured rainwater can also be considered to show compliance
  7. The water requirement and average number of watering days for landscaping shall be considered as 6 liters per sq.m. per day (i.e. 6 liters/ sq.m./ day) for a minimum of 300 days (or) Justify if the water requirement and the average number of watering days for landscaping is less than the above requirement.

d. Reduction of hardscape

At least 50% of the total paved area on site should either be soft-paved and/or shaded under trees/ pergolas/ solar photovoltaics, etc.


  1. Limit use of turf on the site to conserve water and/ or ensure that landscaped area is planted with drought tolerant / native / adaptive species.
  2. Avoid disturbance to the site by retaining natural topography (and/ or) design vegetated spaces on the ground, for at least 15% of the site area.
  3. Restore disturbed site area by designing vegetated spaces over built structures and on the ground, for at least 30% of the site area (including development footprint).
  4. Preserve or transplant at least 75% of existing fully grown trees within the project site / campus.
  5. Plant tree saplings that can mature into fully grown up trees within the next 5 years on the project site, as per the below criteria (including existing and transplanted trees in the project site).
  6. The landscape here refers to soft landscaping which includes only previous vegetation.
  7. Areas planted with turf should not exceed a slope of 25 percent (i.e., a 4:1 slope).
  8. Landscape areas over built structures such as basements, podiums, roofs, etc., can be considered for the calculation.
  9. Retaining ‘Natural Topography’ in its broad sense means preserving the natural features of the terrain such as exposed natural rocks, water body, etc.
  10. Grass medians, grass pavers, jogging track, open-air theatre, parking areas, driveways, walkways, playground, swimming pool, etc., are considered as site disturbances.
  11. Native / adaptive vegetation shall be retained as much as possible.
  12. Potted plants shall not be considered as vegetation.

2. Solar Energy Utilization Bye laws: 10.2 (2)

Efforts need to be taken to ensure energy conservation and a special focus needs to be on renewable energy.

Note: For captive solar power generation, a minimum of 15 % of sanctioned load is the requirement.

a. Installation of Solar Photovoltaic Panels

Solar photovoltaic (PV) systems are direct energy conversion systems that convert solar radiation into electric energy. Roofs of buildings as well as other exposed areas such as parking shade, can be installed with solar PV systems.

b. Installation of Solar Assisted Water Heating Systems

  1. Solar water heating systems should be made in the building for hospitals, hotels, hostels, guest houses, police men/ army barracks, canteens, laboratories and research institutions, schools and colleges and other institutes.
  2. The solar water heating system should be mandatory in the hospitals and hotels, where the hot water requirements are of continuous nature. These buildings must be provided with auxiliary back-up system.
  3. The use of solar water heating systems is recommended in the following type of buildings in Government/ Semi-Government and Institutional buildings where the hot water requirements may not be continuous/ permanent.
  • Guest Houses
  • Police men/Army barracks
  • Canteens
  • Laboratory & Research Institutions where hot water is needed.
  • Hostels, Schools, Colleges and Other Institutes.
  1. The Installation of the electrical back up in all such water heating systems shall be optional depending on the nature of requirements of the hot water.
  2. It is suggested that solar heating systems of the capacity of about 100 liters per day based on thermos phonic with necessary electrical back-up be installed at residential buildings like hostels.
  3. In order to facilitate the installation of the solar water heating systems, the new buildings shall have the following provisions.
  4. All such buildings where solar water heating systems are to be installed will have an open sunny roof area available for installation of solar water heating systems.
  • The roof loading adopted in the design of such buildings should be at least 50 kg per sq. m. for the installation of solar water heating systems.
  • A solar water heating system can also be integrated with the building design. These either can be put on the parapet or could be integrated with the south facing vertical wall of the building. The best inclination of the collector for regular use throughout the year is equal to the local latitude of the place. The Collectors should be facing south. However, for only winter use the optimum inclination of the Collector would be (Latitude + 15 degrees of the south.). Even if the Collectors are built in a south facing vertical wall of building the output from such Collectors during winter month is expected to be within 32% output from the optimum inclined Collector.
  • All the new buildings to be constructed shall have an installed hot water line from the rooftop and insulated distribution pipelines to each of the points where hot water is required in the building.
  • The capacity of the solar water heating system to be installed on the building shall be described on the basis of the average occupancy of the building. The norms for hospitals, hotels and other functional buildings are given below:

Recommended capacity in all building types-

  • An Open area of 3 sq.m would be required for installation of a collector which supplies about 100 liters of water per day. At least 60% of the roof area may be utilized for installation of the system.
  • The specification for the solar water heating system laid down by the Ministry of Non- Conventional Energy Sources can be followed. Flat plate collector confirming to the Bureau of Indian Standards - the latest standard should be used in all such solar water heating systems.

3. Energy Efficiency Bye laws: 10.2 (3)

a. Low Energy Consumption Lighting Fixtures

Lamps, luminaries, ballasts and the controlling systems should be monitored for achieving energy efficiency through artificial lighting.

i. Interior Lighting- for residential buildings

  • Lamps – Lamps used for general lighting scheme shall conform to the following - Point Light Source – All the point light sources installed in the building for general lighting shall be CFL or LEDs or equivalent.
  • Linear Light Source – All the linear light sources installed in the building for general lighting shall be T-5 or at least 4 Star BEE rated TFLs or equivalent.
  • The installed interior lighting power shall not exceed the LPD (lighting power density) value as recommended by ECBC 2007 (Chapter 7, section 7.3)

ii. Exterior Lighting

For Residential complexes, external lighting sources shall have minimum luminous efficacies as per the table given below-

Table 10: Minimum allowable luminous efficacy of various light sources

  • The installed exterior lighting power density for the respective applications shall be in accordance with ECBC 2007 (Chapter 7, section 7.4).
  • Lighting controls shall be installed as recommended by ECBC 2007 for external lighting (Chapter 7, section

b. Energy Efficiency in HVAC systems design (Applicable to all use premises) (mandatory for commercial and desirable for residential):

Energy efficiency in HVAC system design for buildings-

  • The inside design conditions of a conditioned space shall conform to National Building Code 2005 (Part 8, section 3)
  • The outside design conditions shall conform to National Building Code 2005 (Part 8, section 3) • Efficiency of the equipment installed shall comply with ECBC 2007 requirement (Chapter 5, section 5.2.2)
  • The distributed cooling systems (Unitary air conditioners/ Split air conditioners) shall be at least BEE 3 Star rated products.
  • To avoid the conductive heat losses through piping and ductwork insulation shall be provided as recommended by ECBC 2007 (section 5.2.4)

4. Waste Management Bye laws: 10.2 (4)

Facilitate segregation of waste at source to encourage reuse or recycling of materials, thereby avoiding waste being sent to landfills.

a. Segregation of Waste

  1. Building-level Facility - Provide separate bins to collect dry waste (paper, plastic, metals, glass, etc.,) and wet waste (organic), at all the floors and common areas of the building, as applicable. Divert the collected waste to a centralized facility, which is easily accessible for hauling.
  2. Centralized Facility - In addition to dry and wet waste bins, provide separate bins for safe disposal of the following hazardous waste, at the centralized facility:
  • Batteries
  • ‘e’ waste
  • Lamps
  • Medical waste, if any.

Note: The project has to follow the Hazardous Waste Management Guidelines as prescribed by the Ministry of Environment & Forest (MoEF), Government of India.

b. Organic Waste Management

Ensure effective organic waste management, so as to avoid domestic waste being sent to landfills and to improve sanitation & health. Install an on-site waste treatment system for handling at least 50% of the organic and landscape waste generated in the building (including tenant-occupied areas). The generated manure or biogas shall be utilized as appropriate.