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ENERGY & ATMOSPHERE: Pre requisite 1: Commissioning of Building Energy Systems

OBJECTIVE

To verify that the project’s energy-related systems are installed, and calibrated to perform according to the

owner’s project requirements, basis of design and construction documents.

REQUIREMENTS

The following commissioning process activities must be completed by the project team:

Designate an individual as the commissioning authority (CxA) to lead, review and oversee the

completion of the commissioning process activities.

The CxA must have documented commissioning authority experience in at least 2 building projects

The individual serving as the CxA must be independent of the project design and construction

management, though the CxA may be an employee of any firm providing those services. The CxA may be

a qualified employee or consultant of the owner. (A list of commissioning agents recognized by IGBC can

be found here:http://www.igbc.in/site/igbcdir/viewcompanies.jsp?domid=252928&spo=spo)

The CxA must report results, findings and recommendations directly to the owner.

The owner must document the owner’s project requirements.

The design team must develop the basis of design. The CxA must review these documents for clarity and

completeness. The owner and design team must be responsible for updates to their respective

documents.

Develop and incorporate commissioning requirements into the construction documents.

Develop and implement a commissioning plan.

Verify the installation and performance of the systems to be commissioned.

Complete a summary commissioning report.

SUPPORTIVE STRATEGIES

(Source: LEED INDIA NC v1.0)

Engage a CxA as early as possible in the design process. Determine the owner’s project

requirements, develop and maintain a commissioning plan for use during design and

construction and incorporate commissioning requirements in bid documents. Assemble the

commissioning team, and prior to occupancy verify the performance of energy consuming

systems. Complete the commissioning reports with recommendations prior to accepting the

commissioned systems.

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Owners are encouraged to seek out qualified individuals to lead the commissioning process.

Qualified individuals are identified as those who possess a high level of experience in the

following areas:

Energy systems design, installation and operation

Commissioning planning and process management

Hands-on field experience with energy systems performance, interaction, start-up,

balancing, testing, troubleshooting, operation and maintenance procedures

Energy systems automation control knowledge

Owners are encouraged to consider including water-using systems, building envelope systems,

and other systems in the scope of the commissioning plan as appropriate. The building

envelope is an important component of a facility that impacts energy consumption, occupant

comfort and indoor air quality. While this prerequisite does not require building envelope

commissioning, an owner can achieve significant financial savings and reduce risk of poor

indoor air quality by including it in the commissioning process.

The following book by Building Commissioning Association explains the best practices in

commissioning new construction.

http://www.bcxa.org/wp-content/pdf/BCA-Best-Practices-Commissioning-New-Construction.pdf

BENEFITS

A properly commissioned building can result in[1]:

Fewer change orders during the construction process

Fewer call backs for warranty work

Long term tenant satisfaction

Lower energy bills

Avoided equipment replacement costs

Improved profit margin for building owners

Properly trained operational staff

Less maintenance problems

Fast recovery of shutdowns due to equipment failure

Easy to handle Operations and Maintenance

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PURPOSE

Benefits of commissioning include reduced energy use, lower operating costs, fewer contractor callbacks, better building documentation, improved occupant productivity and verification that the systems perform in accordance with the owner’s project requirements.

Source and Reference:

LEEDIndia for New Construction

[1] - http://www.lcsind.org/images/articles/TPC-Article.pdf

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ENERGY & ATMOSPHERE: Pre requisite 2: Minimum Energy Performance

OBJECTIVE

Establish the minimum level of energy efficiency for the proposed building and systems.

REQUIREMENTS

Develop an energy model for the proposed building(s) using appropriate dynamicsimulation modeling software(refer to “Energy Simulation Guidelines” by Bureau of Energy Efficiency (BEE)India) and calculate the baseline building energy consumptionaccording to the building performance rating method outlined in “Energy Assessment Guide”, BEE India.

Demonstrate a minimum 12% performance improvement compared to the baselinebuilding performance demonstrated by Energy Conservation Building Code 2007 (ECBC), BEE India.

(Note: 12% is a ballpark based on the current median EUI of Chennai for new office buildings which is 172 kWh/sq.m and the baseline from ECBC in warm and humid zones)

TECHNIQUES

Steps for meeting ECBC compliance

Source: ECBC public guide

The following three steps may be followed during the design phase:

1. Demonstrate that the building complies with mandatory measures (section 4.2,5.2,6.2,7.2 and 8.2 of

ECBC 2007)

2. Design the building with energy efficiency measures

3. Using an approved simulation software by ECBC, model the energy consumption of the building

using the proposed features to create the proposed design. The model will also automatically

calculate the energy use for the proposed design.

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Purpose

The Confederation of Indian Industry is trying to achieve a 40-50% energy savings.[2]

“Minimum level of energy efficiency in each building is an important criteria as buildings accounts for 45 per cent of emission”

Jamshyd N. Godrej, chairman, CII- Sohrabji Godrej Green Business Centre[5]

Buildings in Chennai are high on energy efficiency according to an ongoing national-level rating exercise and to sustain this progress a minimum energy efficiency standard should be met by every building in new construction category. Currently eight office buildings in the city were rated energy-efficient by the Bureau of Energy Efficiency (BEE), the energy conservation body of the power ministry

[4]

[2]

Sources & References

[1] Council, I. G. (January 2007). Minimum Enegry Performance. LEED INDIA NC Abridged version , 18.

[2] Confederation of Indian Industry. Energy Efficiency Through Green Buildings Concept.

[3] energy efficiency and green building specialists, C. a. (2007, June Saturday, 23). The Hindu. Retrieved from All about Energy Conservation Building Code: http://www.hindu.com/pp/2007/06/23/stories/2007062350010100.htm

[4] The Times Of India, Chennai. (2010, JUlY 23, 05.52am IST). Retrieved from Eight office buildings in the city were rated energy-efficient by the Bureau of Energy Efficiency (BEE), the energy conservation body of the power ministry

[5]The Hindu. (2009, OCTOBER 9,02:34 IST ). Retrieved from Adopt Green Building Code.

[6] Ministry of New & Renewable Energy, G. o. (n.d.). Green Rating for Integrated Habitat. INDIA. Retrieved from National Rating System for Green Buildings: http://greenp.engo.in/files/2012/01/national-rating-system-green-buildings-GRIHA.pdf

[7]TERI Under US Department of State and Bureau Of Energy Efficiency, U. A. (2010). High Performance Commercial Building In India. Retrieved from Case study,Climate Zone, Warm and Humid: http://high-performancebuildings.org/case_study_existingconv_warmhum_chennai.php

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ENERGY & ATMOSPHERE: Pre requisite 3: Ozone Depletion Potential{ODP}

OBJECTIVE

Reduce ozone depletion and support early compliance with the Montreal Protocol,1987.

REQUIREMENTS

Employ 100% zero ODP (ozone depletion potential) insulation; HCFC (hydrochlorofluorocarbon)/ and CFC (chlorofluorocarbon) free HVAC and refrigeration equipments and/halon-free fire suppression and fire extinguishing systems.

SUPPORTIVE INFORMATION

Obtain specification extracts for all proposed refrigerants and gaseous fire suppressionsystems confirming

ODP of each refrigerant and gas.

The ODP and GWP(global warming potential) of various refrigerants is given below[4]:

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Purpose The Ministry of Environment and Forests had brought out Ozone Depleting Substance Regulation Rules 2000 covering various aspects of production, sale, consumption, export, imports of the harmful substances, in January 2000. The substances were divided into seven categories and each group was given time from 2002 to 2016 for a total phase out.

[1]

This criteria is a mandatory one as already a building is constructed in the climatic conditions of Chennai ”GRUNDFOS PUMPS PVT LTD”

[2] which has achieved LEED gold certification by incorporating energy, water and

materials efficiency measures in addition providing superior indoor air quality and overall environment for all its employees. Regarding ozone depletion potential of the building, it has in line with international standards, used refrigerants in the air conditioning system that are environmentally friendly and have very low ozone depleting and global warming potential. Buildingslike these set a benchmarkfor construction of better buildings giving rise to further development in the construction industry.

Sources & References:

[1]The Hindu. (2000, september 18). Retrieved from Ozone depletion being given more importance.

[2]CASE STUDY: GRUNDFOS PUMPS PVT LTD, CHENNAI . (n.d.). Retrieved from http://www.en3online.com/wp-content/uploads/2012/03/3_grundfos_Case_Study.pdf

[3]The Hindu. (2011, May 3). Retrieved from Architect of Change: http://www.thehindu.com/life-and-style/money-and-careers/architect-of-change/article1766383.ece

[4] PEARL rating system version 1.0

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ENERGY & ATMOSPHERE: Credit 1: Energy Monitoring Reporting

OBJECTIVE

Establish continuous monitoring whichallows the energy performance of the building to be recorded and

monitored, and to allow future improvement and understand the use of energy in buildings.

CREDITS: 2

REQUIREMENTS

Demonstrate that easily accessible and clearly labelled energy sub-meters are provided and capable of

monitoring the energy consumption of all tenant areas, and all metering requirements are documented.

The following submissions must be made in order to satisfy this prerequisite:

Energy system schematics illustrating the metering strategy confirming that the metering has been

achieved.

Manufacturer’s data and as-built building services layout drawings clearly indicating the type, extent and

locations of all metering, and central monitoring system.

Photographic evidence confirming installation of specified meters and central monitoring system.

Written commitment from the owner to submit all energy monitoring data to the rating committee

(IGBC)

All meters and sub-meters must have data logging capability and be connected to a central monitoring system so

that information on the building’s energy consumption can be recorded. The monitoring system must have, at a

minimum, the following capability:

Provide hourly, daily, weekly, monthly and annual energy consumption for each end-use

Compare consumption to previous days, weeks, months and years for trend analysis

Determine ‘out-of-range’ values and alert building operators to unusually high Consumption.

Record peak energy consumption for each end-use.

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SUPPORTIVE STRATEGIES

The following nine step for energy metering gives a brief overview of the strategy that may be helpful:

Source: http://www.cibse.org/pdfs/GIL065.pdf, last accessed 11/15/2013

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A detailed guide to the above mentioned nine step strategy can be found in the GIL65 book by Chartered institute

of building services, England. The methods mentioned in the book follows the metric system and the strategies

can be applied to any new building in Chennai as the technologies mentioned are very well available in the

market[1]

.

BENEFITS

Metering per se does not save energy. It is the actions taken as a result of installing and monitoring meters

that can achieve quantifiable energy savings. Meters that are selected and installed correctly provide the

information for the monitoring and targeting process that is an essential part of energy management[2].

Actions taken as a result of installing and monitoring meters often save 5-10%[2] of the energy being

metered. Sometimes they can save more. For example, a meter that identifies pumps being left on for 24

hours, seven days a week, may save 60%[2] of the energy passing through it, whereas a meter measuring

well-controlled services, or a meter that is not read (or not acted on) may save nothing.

PURPOSE

Metering helps to understand where all the energy is going, and enables us to identify and monitor patterns of energy use. Thedata gathered can reveal useful trends between day/night, summer/winter, weekday/weekend.

It can allow operators to:

-compare actual consumption with targets spot things going wrong before it is too late

-maintain one year moving averages to see which way trends are going

Moreover, currently in India thefollowing[3]

issues remain unsolved in energy benchmarking:

- Little or no reliable data available in public domain on actual energy consumption in different types of office/commercial buildings

- No systematic data collection and analysis of building energy usage

- Limited understanding about what are the parameters that influence the energy usage of a building.

Energy metering would help greatly in solving these issues in energy benchmarking which in-turn would create a sense of competitiveness (because benchmarks serves as an excellent baseline “report card”) and shift the construction market towards better building performance.

SOURCES AND REFERENCES:

PEARL rating system, version 1.0

[1] http://www.edmi-meters.com/offices-2.aspx, http://www.hindu.com/2011/01/09/stories/2011010958610200.htm, last accessed 11/15/13

[2] http://www.cibse.org/pdfs/GIL065.pdf

[3] SaketSaraf, 8th

marh 2011, “Benchmarking for energy efficiency in India”, M&V Formalization workshop AEEE.

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ENERGY & ATMOSPHERE: Credit 2: Energy Performance Index

OBJECTIVE

To achieve increasing levels of energy performance beyond the prerequisite standard to reduce

environmental and economic impacts associated with excessive energy use.

CREDITS: 4

FULFILLMENT HIGHLIGHTS

Using the same methodology outlined in Pre requisite 2, calculate the energy performance and calculate the

EPI (kWH/m2/year) of the building as described in“Performance Based Rating and Energy Performance

Benchmarking for Commercial Buildings India”, Satish Kumar, Madhav Kamath, AlokDeshmukh, SaketSaraf,

Sanjay Seth, Sameer Pandita and Archanawalia in BauSIM, Vienna Austri, June 2010.

To achieve this credit submit Energy Model Template summarizing the dynamic energy simulation and

confirming the EPI.

Credit distribution:

EPI (kWh/m2) Credit multipliers:

175-200 x1

150-175 x2

125-150 x3

100-125 x4

<100 x5

(Note: This distribution is based on star rating[1] of office buildings in Chennai by BEE, India)

SUPPORTIVE INFORMATION

EPI indicates the specific energy usage of a building. It is basically the ratio of total energy used to the total

built-up area. This total energy used includes both purchased electricity as well as that generated on-site,

but excludes renewable sources like solar photovoltaic etc. The total built-up area excludes basement and

parking areas[2].

SUPPORTIVE STRATEGIES

Choose the amount of credits to pursue and fix a maximum EPI. Based on that choose a building as

benchmark.

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Benchmarked Building is a building that is similar to the candidate building in terms of its use, location,

physical and operational characteristics based on current knowledge.

Based on you simulations calculate Building Performance Index (BPI):

BPI = Actual energy consumed/energy consumed by the benchmarked building.

Plot graph between actual energy consumed and benchmark building as show in the following example[3]:

COST BENEFIT ANALYSIS

The following is an example which provides motivation towards energy savings and helps overcome initial

cost mentality:

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Source: Buildings: Investing in energy and resource efficiency, United Nations Environment program.

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PURPOSE: New office buildings, malls, and universities are just the cusp of India’s building boom. Anestimated two-thirds of the commercial and high-rise residential structures that will be standing in India in 2030 have yet to be built[4]. That puts India at a critical juncture as it seeks new ways to power its growing economy, and resolve its existing, chronic energy shortages. Buildings already consume 30 percent of India’s energy[5]. These new buildings and their tenants, with their lights, air conditioners, refrigerators, water heaters, washing machines and entertainment systems--could continue to suck the life out of India’s feeble energy grid. Or they could dramatically reduce energy waste and become part of India’s most promising solution for closing its energy gap--efficiency.

The widespread blackouts of July 2012, which left 680 million people[4]—more than twice the population of the United States—without power, revealed the severity of the country’s energy crisis. The Indian government is looking for answers everywhere, planning hundreds of new coal-fired power plants, hydroelectric dams, and expanding solar power and other renewable energy sources. But the cheapest, cleanest, and fastest way for India to bring power to people who need it is energy efficiency. According to McKinsey & Company, India can save $42 billion every year[5] just by reducing energy consumption in buildings.India’s building-occupied area will skyrocket from 8 billion square meters in 2005 to 41 billion square meters in 2030, presenting an enormous opportunity to implement efficiency measures and trim waste.[4]

Coming to the case of Chennai, Chennai office buildings have shown a remarkable development in energy efficiency. The following are some examples of the range of EPIs and star ratings given by BEE India:

HCL Technologies Chennai 199 kWH/m2/year (1 star rating)

CTS Chennai 145 kWH/m2/year (3 star rating)

Ashok Leyland corporate building, Chennai 125 kWH/m2/year (4 star rating)

Sauter race technologies Chennai 92 kWH/m2/year (5 star rating)

SOURCES AND REFERENCE: LEED India NC v1.0

PEARL Rating system v1.0

[1] BEE List of office building ratings, www.beeindia.in

[2]http://www.emt-india.net/ECBC/main.htm, last accessed 11/15/2013

[3] Bencmarking for energy efficiency, M&V formalization workshop AEEE, Chennai, 8th

march 2011

[4] http://theenergycollective.com/peterlehner/230766/indias-next-big-energy-source-energy-efficient-buildings, last accessed 11/15/2013

*5+ “Building India: Accelerating infrastructure projects”, McKinsey & Company, April 2009.

62

ENERGY & ATMOSPHERE: Credit 3: Peak Load Reduction

OBJECTIVE:

To reduce energy demand and consequent increased infrastructure requirements tocater for loads at peak

use times.

CREDITS: 2

FULFILMENT HIGHLIGHTS

Energy consumption during peak load must not be greater than 30% of the baseline load/average annual

load (whichever is higher).

(Note: “30%” is based on the fact that there is 20%[1]energy deficiency during peak loads in Chennai which

leads to power cuts, although 30% is a very low number and maybe very difficult to achieve a higher amount

of credit points would be assigned as this may be considered a big step towards peak load reduction)

Submit a graph from the dynamic energy simulation illustrating the annual electrical load profile of the

proposed building, highlighting the peak and annual average electrical loads.

Also submitcalculations confirming the percentage increase in peak electrical load compared to the annual

average electrical load/baseline.

SUPPORTIVE STRATEGIES

Devising a circuitry that shall efficiently be fitted to the electricity main boards, so that constant monitoring

and switch off of the high powered devices may happen in a customized way. Hence, by having a

configurable system that can be programmed to the convenience of the user, you can save the cost on

electricity which shall otherwise not be wisely used or be wasted unknowingly.

Use renewable energy technologies to serve for excess loads during peak loads.

PURPOSE: As on November 15 2013Most parts in Tamil Nadu(Chennai included) are witnessing load shedding again for four to six hours, due to the failure of the northeast monsoon and growing peak demand[2].

In an article from popular news paper it was found that during summer 2013 government officials were skeptical about tiding over the shortage as all over the country the demand-supply gap had been growing by more than 30%.[3] The TNEB (Tamil Nadu Electricity Board) had called for tenders to purchase over 1,000 MW from

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privategenerators and traders. This was mainly to meet the peak demand from March to May. "From May we can bank on wind energy, but we do not want to rely on it," - A senior EB official.

Sources and Reference: PEARL rating system v1.0

*1+ “Self-Automated Efficient Energy Saver in Domestic Environments “,Imaiya.P, Purnima.K, Gayathri.N,Sneha.D.A, 2012 International Conference on Industrial and Intelligent Information.

[2] http://www.thehindu.com/todays-paper/parts-of-tamil-nadu-facing-46-hours-of-load-shedding/article5353403.ece, last accessed 11/16/2013

[3] http://articles.timesofindia.indiatimes.com/2011-02-23/chennai/28626438_1_power-cuts-acute-power-shortage-demand-shot, last accessed 11/16/2013

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ENERGY & ATMOSPHERE: Credit 4: Renewable Energy

OBJECTIVE

Encourage and recognize increasing levels of self-supply through renewable technologies to reduce environmental impacts associated with fossil fuel energy use.

CREDITS:2

REQUIREMENTS[1]

Renewable energy system with capacity equivalent to 1% of connected load for lighting and space conditioning.

Meet energy requirements for a minimum of 5% of the internal lighting load (for general lighting) or its equivalent from renewable energy sources (solar, wind, biomass, fuel cells, etc).

Energy requirements will be calculated based on realistic assumptions which will be subject to verification during appraisal.

TECHNIQUES[2]

Assess the project for renewable energy potential including solar, wind, geothermal, biomass, hydro, and bio-gas

strategies. When applying these strategies, take advantage of net metering with the local utility.

Purpose

Renewable energy in India’s context is significant for enhancing energy security through diversification of fuel sources, and thereby reducing dependence on fossil fuels, sustainable and environmentally efficient growth and for overcoming power shortages in the country. Recognizing the potential and taking measures for scaling up RE will eventually lead to identification of viable business opportunities that can be tapped by both public and private sector in the near and medium term future.[3]

Only 1 per cent of the country's total power requirement was met by renewable sources, unlike in the case of Denmark and Germany where 25 per cent and 16 per cent respectively of energy requirements were met by wind energy.[4]

The Tamil Nadu Energy Development Agency (TEDA), the nodal agency for development of renewable energy in state of Tamil Nadu showcased the opportunities available for companies in renewable energy field in the state in the event called RENERGY. The key sectors they focused on included solar energy (thermal and photovoltaic), wind, waste-to- energy, biomass and energy efficiency.[5]

The total power demand for Tamil Nadu in 2010-11 was 80,314MU, while Chennai’s demand alone constituted 14,842MU, or 18% of the state’s demand. The city’s demand is likely to be 17% of the state’s (1,19,251MU) in

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2016-17. The transmission and distribution (T&D) losses for Chennai Metropolitan Area are likely to be 13.5% of the total production at the end of 2016-17, and will reduce to 11% in 2021-22, says the study, quoting Tangedco’ssubmission.It is a big challenge for the Tamil Nadu government to meet the increasing demand of Chennai and other cities.[7]

[6]

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[6]

Sources & References:

[1]Ministry of New & Renewable Energy, G. o. (n.d.). Green Rating for Integrated Habitat. INDIA. Retrieved from National Rating System for Green Buildings: http://greenp.engo.in/files/2012/01/national-rating-system-green-buildings-GRIHA.pdf

[2] Council, I. G. (January 2007). Minimum Enegry Performance. LEED INDIA NC Abridged version , 18.

[3] EBTC Blog. (n.d.). Retrieved from Smart technologies for Smart communities: http://www.ebtc.eu/blog/2013/06/smart-technologies-for-smart-communities/

[4] The Hindu. (2012, April 27). Retrieved from Invest in Renewable Energy: http://www.thehindu.com/news/cities/chennai/invest-in-renewable-energy-scientist/article3357622.ece

[5] http://www.thinktosustain.com/2013/02/renergy-2013-conference-and-expo-at-chennai/#.Uohux9LbrK1

[6] TEDA. (2013). Tamil Nadu Energy Development Agency. Retrieved from Establishment of TEDA: http://www.teda.in/

[7] Panchabuta Renewable Energy & Cleantech in India. (013, July 17). Retrieved from Industry dominates consumption in Chennai: http://panchabuta.com/2013/07/17/industry-dominates-consumption-in-chennai/

[8]One World South Asia. (2013, Nov 17). Retrieved from Conference on renewable energy to be held in Chennai, India: http://southasia.oneworld.net/news-you-can-use/event/conference-on-renewable-energy-to-be-held-in-chennai-india-1

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ENERGY & ATMOSPHERE: Credit 5: Cool Building Strategies- Insulation

OBJECTIVE

To determine the most effective solution to reducing a building’s cooling demand by incorporating passive design strategies as a priority.

CREDITS: 4

REQUIREMENTS[4]

Demonstrate that passive design measures have been incorporated into the building design to reduce the external heat gain compared with the baseline building.

Demonstrate percentage reductions (minimum of 10%) in annual external heat gain attributed to passive design measures.

Demonstrate that roofing materials with a high SRI(>78) will be used.

SUPPORTIVE STRATEGIES[4]

Passive design measures are those which require no mechanical systems. This includes, but is not limited to, orientation, fixed shading devices, improvements to building fabric, air tightness etc.

External heat gain is defined as the sum of solar gain, external conduction gain and infiltration gain. Introduce each of the following design measures to the baseline model incrementally and

document the effect each measure has on the annual external heat gain: a. Orientation b. Glazing ratio (both vertical fenestration and skylights) c. Glazing solar heat gain coefficients (SHGC) d. External shading e. Building air leakage rate f. Envelope conductive performance g. Any other passive design measure not cover

SUPPORTIVE DOCUMENTS

Narrative describing the passive design measures to be incorporated within the project; Graph and results table illustrating incremental reductions in the proposed building’s annual

external heat gain (kWh/m2) as outlined within the Calculations and Methodology section;

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Drawings (section, plan and elevation) as necessary to fully describe all passive design measures integrated into the building design;

Extracts from specifications relating to construction thermal performance parameters and building envelope air tightness specifications and air testing methodology (where applicable); and

Roof drawings and specifications confirming all roof areas except those covered by mechanical plant, shading devices, renewable technologies and designated vegetated roofs use materials with a SRI 78.

PURPOSE In a hot city like Chennai, a portion of the sun's incident energy inevitably finds its way into the buildings on which its rays fall. In the summer time, this unwanted heat energy causes discomfort and requires the use of extra energy for air-conditioning. As the summertime sun rises high in the sky, the sun's radiant energy falls mainly on the roof, with east and west walls of buildings also receiving a significant share.

For untreated normal roofs, the surface temperature is up to 25 degrees centigrade higher than the ambient peak temperature. In roofs that have been heat-proofed, the difference between the roof and ambient temperatures can fall to as low as 10 degrees centigrade. In other words, the room temperature can be effectively lowered by as much as 15 degrees centigrade.

[5]

HEAT REFLECTIVE MATERIALS:By re-radiating 98.76 per cent of sunrays, heat reflective compounds prevent the roof from getting heated up during daytime. Laboratory tests have proved that application of the compound lowers the temperature inside the building substantially. By reducing the use of air conditioners and electric fans, it helps save power.

Heat-reflective and insulating compounds are gaining acceptance as a cost-effective method of minimising solar heat. Fosroc offers two compounds under the Brushbond brand, namely Coolcoat and TI Flexicoat. Both are water-based emulsions comprising polymers and specially- designed hollow ‘microspheres’ less than 100 microns in diameter. While Brushbond is a polymer-based compound, Flexicoat is also elastomeric and acrylic. Both compounds come in the form of a white paste that can be directly applied.Flexicoat is also capable of bridging hairline cracks caused by thermal movement[1]

The placement of reflective tiles on the terrace reduces heat penetration by 90%.[2]

This credit is introduced to encourage use and development of innovative technologies in terms of insulation or non insulating materials but causing cooling of building.

SOURCES & REFERENCES [1] The Hindu. (2008, February 23). Retrieved from Property plus:

[2]The Times Of India, Chennai. (2010, March 5). Retrieved from Now,Homes in Chennai go green: http://articles.timesofindia.indiatimes.com/2010-03-05/chennai/28138768_1_green-building-house-water

[3]The Hindu. (2013, June 14). Retrieved from Hot Spots & Cold Zones : How weather differs within Chennai: http://www.thehindu.com/news/cities/chennai/hot-spots-and-cold-zones-how-weather-differs-within-chennai/article3886212.ece

[4]Pearl Building Rating System: Design & Construction, Version 1.0, April 2010

[5]The Hindu,http://www.hindu.com/pp/2005/03/26/stories/2005032600080100.htm