1

CHAPTER 1

INTRODUCTION

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1. INTRODUCTION

1.1 THE GREEN CONCEPT

Green is not just a color today!

With rising energy costs, tightening budgets, increasing populations and

diminishing resources, it is becoming increasingly important that business and

individuals conserve or ―go green‖

Green – or sustainable- building practices help to create healthier and

more resource – efficient models of:

- Construction

- Renovation

- Operation

- Maintenance

- Demolition

Green symbolizes environment friendly practices in all facets of

human endeavor

1.2 WHAT IS A GREEN BUILDING?

A green building depletes the natural resources to the minimum during

its construction and operation.

Main aim is to

- minimize the demand on non renewable resources

- maximize the utilization efficiency of these resources, when in

use

- maximize the reuse, recycle and utilization of renewable

resources.

Optimizes the use of on-site resources sinks by bio-climatic architectural

practices.

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Uses efficient equipments to meet its lighting, air condition and other

needs

Use efficient waste and water management practices

Provides comfortable and hygienic indoor working conditions.

In sum, the following aspects of building design are looked into an

integrated way in a green building:

- Site planning

- Building envelope design

- Building system design (HVAC, heating , ventilation and air

conditioning, lighting, electrical and water heating)

- Integration of renewable energy resources to generate energy

on site.

- Water and waste management

- Selection of ecologically sustainable materials(with high

recycled content, rapidly renewable resources with low emission

potential, etc.)

- Indoor environmental quality

1.3 WHY MAKE A GREEN BUILDING ?

All over the world we are finally beginning to recognize the threat that building

construction is posing to the civilization. Buildings have major environmental

impacts over their life cycle. There are various problems arising in the present

scenario:

PROBLEM 1- BUILDINGS CONSUME:

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40% of all energy

Figure 1.1 - Distribution of energy consumed by a conventional building

71% of all electricity

50% of all gas demand

12% of all fresh water

88% of all potable water

40% of all wood, steel and other raw materials

1 acre gets developed every 12 seconds!!!

PROBLEM 2- BUILDING POLLUTE:

Building contribute 40-50% of green house gas (GHG) emissions

Building creates 65% of all solid waste, 90-95% of construction and

demolition waste could be recycled

Figure 1. 2 - A pie chart showing the percentage of construction waste obtained from various activities.

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Indoor pollution often 2-100 times worse than outdoors

PROBLEM 3- IMPACT OF ASIA ON GLOBAL WARMING

In next 25 to 30 years

Energy consumption of developing Asian countries will more than

double

CO2 emissions will increase more than three fold

Electricity generation in asian countries is expected to make the greatest

contribution to CO2 emmisions

- APERC,2006

SOLUTION IS A GREEN SUSTAINABLE BUILDING

Energy efficiency is the most effective way to address climate change

Energy efficiency is the cheapest source of additional energy supply

and the most cost effective way to reduce GHG

An efficient sustainable building will :

- reduce energy usage and life cycle cost

- create a better environment for occupants

- reduce use of water and consumption of natural resources

- reduce generation of pollution and CO2 emission.

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1.4 ECONOMIC BENEFITS

PERCEPTION : Green buildings are costlier

REALITY :

Considerable research and analysis has been carried out with regards to the cost

impacts of a green building. The cost could be slightly higher than conventional

building. But then, this need to be seen in a different paradigm. The question is how do

we compare the cost? There needs to be a baseline cost for all comparisons to be alike.

The incremental cost is always relative and depends on the extent of eco-friendly

features already considered during design. The incremental cost would appear small if

the baseline design is already at a certain level of good eco-design; It would appear

huge if the base design has not considered green principals.

The second and rather critical paradigm is to look at the incremental cost in relation to

the life cycle cost. This kind of an approach could be revealing. Who knows, a building

would last for a 50 years or 60 years or 100 years! Over its life cycle, the operating

cost would work out to 80-85 % while the incremental cost which is one-time cost is

only about 8-10%

Building Year

Constructed

Built in area

(sq.ft.)

% increase in cost Payback

(years)

CII-Godrej GBC,

Hyderabad

2003 20,000 18% 7

ITC Green Center ,

Gurgaon

2004 1,70,000 15% 6

Wipro,

Gurgaon

2005 1,75,000 8% 5

Grunfos Pumps, 2005 40,000 6% 3

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Chennai

Technopolis,

Kolkata

2006 72,000 6% 3

Spectral services,

Noida

2007 15,000 8% 4

HITAM,

Hyderabad

2007 78,000 2% 3

Table 1.1 – Payback periods of Green buildings

There is a decreasing trend in the incremental cost over the years. This trend would

continue and we all look forward to the day when the cost of green building will be

lower than a conventional building.

Green buildings are well poised to grow in the years to come which would provide

tremendous opportunities to all the stake holders.

The investment opportunities in green buildings is estimated to be about 2000 crores

by the year 2008.

1.5 GREEN BUILDING MOVEMENT IN INDIA

0

10

20

30

40

50

60

70

80

2002 2003 2004 2005 2006 2007

LEED REGISTERED

BUILDINGS

India is witnessing tremendous growth in infrastructure and construction development.

The construction industry in India is one of the largest economic activities and is

growing at an average rate of 9.5% as compared to the global average of 5%. As the

Figure 1.3 – Number of LEED registered buildings.

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sector is growing rapidly, preserving the environment poses lot of challenge and at the

same time presents opportunities. The construction sector therefore needs to play its

role and contribute towards environmental responsibility.

The green building movement in India is a step in this direction-to minimize the

negative impact of construction activity on the environment

The Green Building movement in India spearheaded b CII has gained tremendous

impetus over the last six years. From a modest beginning of 20,000sq.ft of green

building foot print in the year 2003, India is today witnessing atleast 20 million sq.ft of

green building foot print with about 80 green buildings being constructed

The rapidity of the green building movement can be seen by the spiraling growth of

clearly measurable green building criteria as indicated in the following table

No. Criteria 2001 Till date

1 CEOs & senior people involved 50 2000

2 No. of professionals trained on

LEAD rating

10 2500

3 No. of registered Green

Buildings

1 80

4 Built in area (sq. ft.) 0 25 million

5 Green building products and

equipments

5 50

Table 1.2 – Increasing green movement

1.6 GREEN CONCEPT IN INSTITUTIONAL BUILDING

The green movement is gaining momentum rapidly. But, is the rate enough?

And the answer is of course ‗NO‘. It certainly needs more and more people‘s

involvement to get visible and desired result. One can‘t blame anyone for non-

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involvement if they aren‘t aware of green concept. Certainly, they need to know it to

get involved. The key is awareness.

To increase the awareness what would be a better place than an educational

institution. Here thousands of students come every year. They stay, they learn, they

grow here. It‘s the place to share new ideas and concepts. So if they get to see a live

example of green initiative, they won‘t only know, but will be able to judge and see the

benefits. They too may start thinking green and finding out new and better green ways.

And then thousands of students go out every year to different places of their work field.

They of course take their ideas with them and influence the people at their work place,

which in turn further increasing the awareness.

The idea is to increase the awareness at roots.

1.7 RATING SYSTEMS FOR GREEN BUILDINGS

1.7.1 LEED-US

The United States Green Business Council (UGBC) has developed The

Leadership in Energy and Environmental Design (LEED) Green Building

Rating System, which is the internationally accepted benchmark for design,

construction and operation of high performance green buildings. LEED gives

Building owners and operators the tools they need to have an immediate and

measurable impact on their building‘s performance. LEED promotes a whole

building approach to sustainability by recognizing performance in 5 key areas

of human and environmental health

1. Sustainable site development

2. Water savings

3. Energy Efficiency

4. Material selection

5. Indoor Environmental Quality

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POINTS

Prerequisites Mandatory

1. Sustainable site 13 points

2. Water efficiency 6 points

3. Energy and Atmosphere 17 points

4. Material and Resources 13 points

5. Indoor Environmental Quality 15 points

6. Innovation and design process 5 points

Total 69 points

RATING POINTS

LEED-Certified 26-32

LEED-Silver 33-38

LEED-Gold 39-51

LEED-Platinum 52-69

Table 1.3 – LEED prerequisites and rating points.

1.7.2 TERI GRIHA

The Energy and Resources Institute –Green Rating for Integrated Habitat

Assessment

Internationally, voluntary building rating systems have been instrumental in raising

awareness and popularizing green design. However, most of the internationally

devised rating systems been tailored to suit the building industry of the country

where they were developed. TERI, being deeply committed to every aspect of

sustainable development, took upon itself the responsibility of acting as a driving

force to popularize green building by developing a tool for measuring and rating

buildings environmental performance in context of India‘s varied climate and

building practices. This tool, by the quantitative and qualitative assessment criteria,

would be able to ‗rate‘ a building on the degree of its greenness. The rating would

be applied to new and existing building stock of varied functions-commercial,

residential and institutional.

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1.7.3 MINERGIE

MINERGIE is a registered quality label for new and refurbished low-energy

consumption buildings. This label is mutually supported by the Swiss

Confederation, the Swiss Cantons and the Principality of Liechtenstein along with

Trade and Industry. The label is registered in Switzerland and around the world and

is thus protected against unlicensed use. The Minergie label may only be used for

buildings, services and components that actually meet the Minergie standard.

Building to Minergie standards means providing high-grade, air-tight building

envelopes and the continuous renewal of air in the building using an energy-

efficient ventilation system. Specific energy consumption is used as the main

indicator to quantify the required building quality. In this way, a reliable

assessment can be assured. Only the final energy consumed is relevant.

At present around 13% of new buildings and 2% of refurbishment projects are

Minergie certified. These are mostly residential buildings. The goals of the Swiss

national Swiss Energy Infrastructure and environment program call for 20% of new

construction and 5-10% of refurbishment projects to be Minergie certified.

The Minergie standard is somewhat comparable to German KfW40 (new buildings)

and KfW60 (refurbishment) standards.

1.7.4 BREEAM

BREEAM (Building Research Establishment‘s Environmental Assessment

Method) is the world‘s leading and most widely used environmental assessment

method for buildings, with over 115,000 buildings certified and nearly 700,000

registered. It sets the standard for best practice in sustainable design and has

become the de facto measure used to describe a building‘s environmental

performance. Credits are awarded in ten categories according to performance.

These credits are then added together to produce a single overall score on a scale of

Pass, Good, Very Good, Excellent and Outstanding. The operation of BREEAM is

overseen by an independent Sustainability Board, representing a wide cross-section

of construction industry stakeholders.

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Objectives of BREEAM:

· To provide market recognition to low environmental impact buildings

· To ensure best environmental practice is incorporated in buildings

· To set criteria and standards surpassing those required by regulations and

challenge the market to provide innovative solutions that minimize the

environmental impact of buildings

· To raise the awareness of owners, occupants, designers and operators of the

benefits of buildings with a reduced impact on the environment

· To allow organizations to demonstrate progress towards corporate environmental

objectives

Type of projects that can be assessed using BREEAM

A BREEAM assessment can be carried out at the above stages for the following

types of building project:

· New Construction

· Major refurbishment to existing buildings

· New construction to an existing building i.e. an extension of existing building

· A combination of new construction and major refurbishment to an existing building

· New construction or major refurbishment, which forms part of a larger mixed use

building

· Existing building fit-out

ENERGY STAR

Green Star is a voluntary environmental rating system for buildings in Australia. It

was launched in 2003 by the Green Building Council of Australia.

The system considers a broad range of practices for reducing the environmental

impact of buildings and to showcase innovation in sustainable building practices,

while also considering occupant health and productivity and cost savings.

Nine categories are assessed with the Green Star tools:[1]

Management

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Indoor environment quality

Energy

Transport

Water

Materials

Land Use & Ecology

Emissions

Innovation

1.8 TERI (THE ENERGY AND RESOURCES INSTITUTE)

1.8.1 Introducing TERI

A dynamic and flexible organization with a global vision and a local focus, TERI

(The Energy and Resources Institute ) was established in 1974. While in the initial

period, the focus was mainly on documentation and information dissemination,

research activities in the fields of energy, environment, and sustainable

development was initiated towards the end of 1982. All these activities were rooted

in TERI‘s firm conviction that efficient utilization of energy, sustainable use of

natural resources, large - scale adoption of renewable energy technologies, and

reduction of all forms of waste would move the process of development towards

the goal of sustainability.

A unique developing-country institution, TERI is deeply committed to every aspect

of sustainable development. From providing environment-friendly solutions to rural

energy problems to helping shape the development of the Indian oil and gas sector;

from tackling global climate change issues across many continents working in

partnership with local communities to help conserve forests ; from advancing

solutions to the growing urban transport and air pollution problems to promoting

energy efficiency in the Indian industry, the emphasis has always been on finding

innovative solutions to make the world a better place to live in. Although TERI‘s

vision is global, its roots are firmly entrenched in the Indian soil. All activities in

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TERI move from formulating local- and national-level strategies shaping global

solutions to critical energy and environment-related issues. To this end TERI has

established regional centres in Bangalore, Goa, Guwahati, and Kolkata (recently

Mumbai also), and has a presence in Japan and Malaysia. It has set up affiliate

institutes: TERI–NA (Tata Energy and Resources Institute, North America)

Washington, DC, USA, and TERI–Europe, London, UK.

As an extension of its work on environment management, TERI has designed

TERI– GRIHA (TERI-Green Rating for Integrated Habitat Assessment).

1.8.2 TERI green building rating system: TERI–GRIHA

1.8.2.1 The context

Internationally, voluntary building rating systems have been instrumental in raising

awareness and popularizing green design. However, most of the internationally

devised rating systems have been tailored to suit the building industry of the

country where they were developed. TERI, being deeply committed to every aspect

of sustainable development, took upon itself the responsibility of acting as a driving

force to popularize green building by developing a tool for measuring and rating a

building's environmental performance in the context of India's varied climate and

building practices. T his tool, by its qualitative and quantitative assessment criteria,

would be able to ‗rate‘ a building on the degree of its ‗greenness‘. The rating would

be applied to new and existing building stock of varied functions – commercial,

institutional, and residential.

1.8.2.2 The challenges

The Indian building industry is highly decentralized, involving diverse stakeholders

engaged in design, construction, equipment provision, installation, and renovation

of buildings. Each group may be organized to some extent, but there is limited

interaction among the groups, thus disabling the integrated green design and

application process. Hence, it is very important to define and quantify sustainable

building practices and their benefits. It is also imperative to delineate the role of

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each actor in ensuring that the building consumes minimal resources in its entire

life cycle and leaves behind minimal environmental footprint.

1.8.2.3 The benefits

TERI's green building rating will evaluate the environmental performance of a

building holistically over its entire life cycle, thereby providing a definitive

standard for what constitutes a ‗green building‘. The rating system , based on

accepted energy and environmental principles, will seek to strike a balance between

the established practices and emerging concepts, both national and international.

The guidelines/criteria appraisal may be revised every three years to take into

account the latest scientific developments during this period.

On a broader scale, this system, along with the activities and processes that lead up

to it, will benefit the community at large with the improvement in the environment

by reducing GHG (greenhouse gas) emissions, improving energy security, and

reducing the stress on natural resources.

Some of the benefits of a green design to a building owner, user, and the society as

a

whole are as follows :

§ Reduced energy consumption without sacrificing the comfort levels

§ Reduced destruction of natural areas, habitats, and biodiversity, and reduced soil

loss from erosion, etc.

§ Reduced air and water pollution (with direct health benefits)

§ Reduced water consumption

§ Limited waste generation due to recycling and reuse

§ Reduced pollution loads

§ Increased user productivity

§ Enhanced image and marketability

1.8.3 EVALUATION CRITERION AND SCORING POINTS

Criterion Description Points

1 Design to include existing site features 2

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2 Preserve and protect landscape during

construction

5

3 Soil conservation 4

4 Reduce hard paving on site 2

5 Enhance outdoor lighting system efficiency 4

6 Plan utilities efficiently and plan optimize

site circulation

3

7 Provide at least minimum level of sanitation

facilities for construction workers

2

8 Reduce air pollution during construction 2

9 Reduce landscape water requirement 3

10 Reduce building water use 2

11 Efficient water use during construction 1

12 Optimize building design to reduce

conventional energy demands

6

13 Optimize energy performance of building

within specified comfort

12

14 Utilization of fly ash in building structures 6

15 Reduce volume, weight and time of

construction by adopting efficient

technology

4

16 Use low energy materials in interiors 4

17 Renewable energy utilization 3

18 Renewable energy based hot water system 2

19 Waste water treatment 2

20 Water recycle and reuse 5

21 Reduction in waste during construction 2

22 Efficient waste segregation 2

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23 Storage and disposal of waste 2

24 Resource recovery from waste 2

25 Use of low VOC paints 4

26 Minimize ozone depletion substances 3

27 Ensure water quality 2

28 Acceptable outdoor and indoor noise levels 2

29 Tobacco and smoke control 1

30 Energy audit and validation Mandatory

31 Operation and maintenance protocol for

electrical and mechanical equipments

2

32 Bonus 4

Total 100

Table 1.4 – Evaluation criterion of TERI-GRIHA

1.8.4 RATING

RATING POINTS

1 STAR 51-60

2 STAR 61-70

3 STAR 71-80

4 STAR 81-90

5 STAR 91-100

Table 1.5 – Rating points of TERI-GRIHA

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CHAPTER 2

METHODOLOGY

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2.1 AIM OF THE PROJECT

The aim of this design thesis is to study the green concepts, understanding their

viability and using them to design an administrative block, which will prove to be

an iconic building, a standing example of a green building which would be healthy

for the people inside as well as outside. Such design can be termed as a ―sustainable

design‖

At the same time, the idea of taking an institutional administrative building as a

typology is to prove that the focus is not just environment but also spreading the

green concept. The design aims at providing an eco-friendly place, which is not

only healthy for its occupants and environment but also increasing the awareness.

2.2 SCOPE & LIMITATIONS

The concept of green buildings though popular among professional has yet not

reached the common man properly.

The main idea behind the project is to make the green concept assessable to the

common man so that they can appreciate its importance.

There are various misconceptions regarding the cost and economic viability of

green buildings which needs to be clarified.

The main challenge of this design problem will be inter-linking the various

functions performed by the building and at the same time not compromising with

the energy efficient aspect of the structure.

2.3 RESEARCH AND PRE- DESIGN STUDY

The entire thesis revolves round the idea behind the topic which was to find out the

relevance of green architecture and study the parameters and requirements of a

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green building. The idea is also to apply these concepts in the design solution and

get a first hand experience in designing a green building and face the challenge.

CHAPTER 1 – INTRODUCTION

This chapter explains the meaning of a green building. It tells about the importance

of green building in today‘s scenario and proves its economical viability. It further

explains the concept of an administrative building in an educational institution and

also the need of such a project. It also talks about the various rating systems and

points given to rate a building green

CHAPTER 2 – METHODOLOGY

This chapter goes on explaining the exact method by which the thesis is going to be

carried out including a chapter to chapter description of the design thesis, including

the main aims and objectives of the thesis , with the scope and limitations of the

topic including the main areas that will be concentrated during the thesis

CHAPTER 3 – DATA COLLECTION

The data collection would include all relevant data required in designing a Green

administrative building.

The data to be collected would be decided from the program requirements and the

inferences from case studies. This data would further be used as references during

the design process.

The data collected is

Various green measures and their applications according to TERI-GRIHA.

Hierarchy of administrative staff of N.I.T.

Office spaces and other space requirements.

Apart from this data collection analysis will be done on

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Efficient landscaping

Glass in green architecture

Utilization of fly ash in building structures

Rain water harvesting

Waste water management

The data collection will also include guidelines given by TERI for designing a

building with green features in sync.

CHAPTER 4 – CASE STUDY

The main aim of this chapter would be to put forward the kind of functions present

in parallel case studies of green buildings, realizing their positive and negative

points.

The chapter will end in an analysis and conclusion which will finally help in the

program requirements, site selection and limits of the site.

The case studies selected are

1. CESE BUILDING, IIT KANPUR.

2. MNNIT ALLAHABAD.

CHAPTER 5- SITE SELECTION AND ANALYSIS

The chapter would include the reason for selecting the site and the site details.

CHAPTER 6- DESIGN APPROACH

The chapter will explain the initial design concept for development of building form.

CHAPTER 7- FINAL PROPOSAL

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CHAPTER 3

GREEN DESIGN

CONCEPTS

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3.1 Design to include existing site features

3.1.1 Objective

The natural functions of a plot of land (hydrologic, geologic, and microclimatic)

can be seriously disrupted by the placement of a building on it. The design of a

green building will factor in the ways in which the natural site features can be

protected or even restored.

Layout the site activities and building requirements after carrying out detailed

site analysis so as to ensure sustainable site development in tune with its

topographical,

climatic, and ecological character.

3.1.2 Site inventory and design impacts

Table 3.1 – Site inventory and design impacts

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3.2 Reduce hard paving on site/and or provide shaded hard paved

surfaces

3.2.1Objective

To reduce hard paving on - site (open area surrounding building premises)

and/or provide shade on hard paved surfaces to minimize the heat island effect

and imperviousness of the site.

3.2.2 Heat island effect

Dark coloured and constructed surfaces are prone to absorption and retention of

solar energy. The retained solar energy also gets re-radiated to atmosphere

during times when ambient temperature gets cooler. This gives rise to warmer

temperatures in urban landscapes, which have large areas of constrained

surfaces low on reflectance. This phenomenon of increased temperature in

urban landscape is called heat island. Principle surfaces that contribute to the

heat island effect include streets, sidewalks, parking lots, and buildings. Heat

island effect can be minimized by use of shading or reflective surfaces. As

mentioned, hard paved surfaces are one of the major constraints of heat in land

effect.

In addition to causing heat island effect, hard pavements also reduce

perviousness of site. Enhanced perviousness of site minimizes storm water run-

off and is beneficial for localized aquifer recharge. This method aims to

encourage design measures to minimize negative impacts of the paved areas.

3.2.3 Best practices

Planting trees, bushes, or a properly planned landscaping can help reduce the

heat island effect by reducing ambient temperatures through evapo-

transpiration. Plant vegetation around the building to intercept solar radiation

and to shade the walls and windows of buildings (with S, SW or SE exposure)

to prevent heat gain. This would also help in reducing air-conditioning load/use.

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Use light coloured, reflective roofs having an SRI (solar reflectance index) of

50% or more. The dark colored, traditional roofing finishes have SRI varying

from 5% to 20%. The fine example of higher SRI is the use of broken china

mosaic, light coloured tiles as roof finish, which reflects the heat off the surface

because of high solar reflectivity, and infrared emittance which prevents heat

gain.

Use commercially available, high solar reflective (albedo) roof coatings or heat

reflective paints on roofs used to shade paved areas. Don't use stone mulches

such as fine gravel, crushed granite or pebbles in unplanted areas immediately

adjacent to buildings, as they can heat up, reflect solar radiation inside, and also

cause glare.

Use high albedo or reflective pavements to keep parking lots, pavements and

inside roads cool because the increase in albedo decreases the pavement

temperature approximately by 8°F for a change in albedo of 0.1.

Use light coloured aggregates or ‗whitetop‘ the pavements with 50 mm thick

layer of cement concrete. Stabilize the pavements with porous or permeable

materials such as sand, crushed bricks, broken mosaic tiles or stones where the

soil is stable or the traffic load is quite low. Recycled materials such as

demolished concrete (rubble), broken china and mosaic tiles could also be used.

3.2.4 Commitments

Total paved area of the site under parking, roads, paths, or any other use not to

exceed 25% of the site area or net imperviousness of the site not to exceed the

imperviousness factor as prescribed by the National Building Code of India,

Bureau of Indian Standards,2005; Part 9 (Plumbing services) Section

5.5.11.2.1, whichever is more stringent.

Total surface parking not to exceed the area as permissible under the local

bylaw and

pavement/grass pavers, or

vegetated roof/pergola with planters, or

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50% of the paved area (including parking) to be topped with

finish having solar reflectance of 0.5 or higher.

3.3 Enhance outdoor lighting system efficiency

3.3.1 Objective

Enhance energy efficiency of outdoor lighting and promote usage of renewable

forms of energy to reduce the use of conventional/fossil fuel based energy

resources.

Luminous efficacy of external light sources used for outdoor lighting shall

equal or exceed as specified.

3.3.2 Minimum allowable values of luminous efficacy of lamps for outdoor

lighting

Light source Minimum allowable luminous efficacy

(lm/W)

CFL (Compact fluorescent lamps) 50

FL (Fluorescent lamps) 75

MH (Metal Halide) 75

HPSV (High pressure sodium vapour lamp) 90

All outdoor lightings to be fitted with an automatic on/off switch.

A minimum 25% of the total number of outdoor lighting fixtures to be powered

by solar energy. Outdoor lighting system includes

(i) Security lighting,

(ii) Street lighting,

(iii) Landscape lighting,

(iv) Façade lighting, and

(v) Parking lighting

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3.4 Reduce landscape water requirement

3.4.1 Objective

To reduce the landscape water requirement for so as to minimize the load on the

municipal water supply and depletion of groundwater resources.

3.4.2 Best practices to reduce water usage for landscaping

Xeriscaping

Xeriscape means the conservation of water and energy through creative

landscaping. This word is derived from the Greek word Xeros meaning dry and

these plants can live, once established, with little or no supplemental watering.

Some are drought tolerant. It is recommended that:

§The landscape should be a mix of native shrubs and xeriscape plants.

Reduce the lawn area, and plant more of trees that require no water after

establishment.

Plant palm trees which are xerophytic such as Phoenix dactylifera,

Yucca starlite.

Use ground covers such as Asparagus sprengeri, which is succulent,

Pandanus dwarf which is xerophytic, and

Bougainvillea which is a climber.

Drip irrigation

Drip irrigation system or sub-surface drip irrigation system results in saving of

water as it avoids loss of water due to run-off, deep percolation, or evaporation.

Sprinkler irrigation

Sprinkler irrigation is a method similar to natural rainfall in which water is

distributed through a system of pipes. For maintaining uniform distribution of

water, the pump supply system, sprinklers and operating conditions must be

designed appropriately. Sprinklers are most suited to sandy soils with high

infiltration rates. The average application rate should be less than the basic

infiltration rate of the soil so as to avoid surface ponding and run-off. It is better

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to use sprinklers that produce fine sprays and not those that produce larger

water droplets.

Native vegetation

Native vegetation is original to a particular place, including trees, shrubs, and

other plants

Evapo-transpiration rate

The potential evapo-transpiration rate (PET) is the climate factor, refers to the

amount of water required by the plant for healthy growth (depending on the

climate). Evapo-transpiration rate determines the rate at which plants lose water

through evaporation. It is affected by humidity and temperature at a given time.

These rates vary with the season and are different for different months. The data

is available with the Indian Meteorological Department for each city.

3.4.3 Efficiencies of irrigation systems

Irrigation efficiency refers to the ability of an irrigation system to deliver water

to plants without evaporation or other means of water loss.

Irrigation system Efficiency

Micro, drip 85%

Micro, spray 80%

Multiple sprinkler 75%

Sprinkler, large guns 70%

Seepage 50%

Crown flood 50%

Flood 50%

3.4.4 Commitment

Design the landscape so as to reduce water consumption by minimum 30%.

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3.5 Reduce the water use by the building

3.5.1 Objective

To reduce the water consumption in the building by using efficient fixtures.

3.5.2 Best practices

1) Use of efficient plumbing fixtures, sensors, auto valves, pressure reducing

device wherever possible can result in significant reduction in water consumption

2) Water efficient fixtures

§ Conventional toilets use 13.5 litres of water per flush. Low flush toilets

are available with 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 smaller flush for liquid waste.

§ Flush valves with 20–25 mm inlets can be used for restricting the water

flow

§ Composting toilets

§ Water-efficient urinals

The conventional urinals use water at a rate of 7.5–11 litres per 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.

3) Auto control valves

Installation of magic eye solenoid valve (self-operating valves) can result in water

savings. The sensor taps has automatic on and off flow control. It is not only

convenient and hygienic but also an excellent water saving device that can work

under normal water pressure. It functions with parameters such as distance and

timing.

4) Pressure reducing device

Aerators and pressure inhibitors for constant flow. Use of aerators can result in

flow rates as low as 2 litres per minute, which is adequate

3.5.3 Commitment

Reduce the total water consumption in the building by a minimum of 25%

30

3.6 Optimise building design to reduce conventional energy demand

3.6.1 Objective

To apply solar passive measures including day lighting to reduce the demand on

conventional energy for space conditioning and lighting systems in buildings.

3.6.2 Passive solar concept

Buildings should minimize their dependence on conventional systems of

heating, cooling, ventilation and lighting which consume electricity produced

from non renewable sources of energy. Solar passive buildings are designed to

achieve thermal and visual comfort by using natural energy sources and sinks

eg, solar radiation, outside air, wet surfaces, vegetation etc. The solar passive

design strategy should vary from one climate to another. For example in

Hyderabad which falls in Hot & dry climate zone, evaporative cooling could be

very effective, however, in warm & humid climate zone water has to be

removed from air to provide comfort.

3.7 Optimize energy performance of building within specified comfort

limits

3.7.1 Objective

To optimize energy use in energy systems in buildings that maintains a

specified indoor climate conducive to the functional requirements of the

building

3.7.2 Commitments

Follow mandatory compliance measures (for all applicable buildings) as

recommended in the Draft energy conservation building code of the Bureau of

Energy Efficiency, Government of India.

31

Show that energy consumption in energy systems in a building under a

specified category is less than the benchmarked energy consumption figure. The

energy systems include air conditioning, indoor lighting system, water

heating, air heating and air circulation devices within the building.

The annual energy consumption of energy systems in a fully air

conditioned building for day use in a composite climate should not exceed 140

kWh/m2 (kilowatt hour per square metre) (benchmarked energy consumption

figure).

The annual energy consumption of energy systems in a fully non-air

conditioned building for day use should not exceed 26 kWh/m2 (benchmarked

energy consumption figure).

In a building that includes air– conditioned and non-air conditioned

areas, the annual energy consumption of energy systems in totally air

conditioned areas for day use should not exceed 140 kWh/m2 and the annual

energy consumption of energy systems in totally non-air conditioned areas for

daytime operation should not exceed 26 kWh/m2.

Quantify energy usage for all electrical, mechanical, and thermal

systems for which either electrical or thermal energy is being used and which

are being used to provide lighting, air conditioning, ventilation, heating (water

and air), and air circulation.To convert thermal energy to electrical energy

following table can be used.

Energy conversion factors Energy unit Conversion factor for kWh

Litres of LDO (light diesel oil) 8.3

Litres of HSD (high speed diesel) 8.5

kg of LPG (Liquefied petroleum gas) 13.9

SCM (Standard cubic metres) of PNG (Pipe natural gas) 7.0

32

3.8 Utilization of flyash in building structure

3.8.1 Objective

To use low embodied energy industrial waste fly ash as the construction material.

Fly ash, an industrial waste having the properties of cement and very low embodied

energy is used in combination with cements that are high in embodied energy.

3.8.2 Best practices for flyash

Use ready mix concrete or high-volume fly ash concrete for construction

(commercially available from L&T, ACC etc.) or use PPC concrete for

construction (commercially available by ACC suraksha, Lafarge cement, L&T

cement, Jaypee Buniyad, Pn'sm Champion etc, PPC must meet the requirements of

IS 1489:1991}.

Portland pozzolona cement

This cement is equivalent to OPC (Ordinary portland cement) in mechanical

strength, setting, and hardening and is an alternative to OPC, with an additional

advantage of having mild sulphate resistance.

Pozzolana cement or PPC (Portland Pozzolana Cement) is a mixture of ordinary

Portland cement (65%-85%) and a pozzolana (15%-35%). Sometimes, PPC

concrete develops strength at a slower rate than OPC concrete. Calcined clay and

fly ash are the most common pozzolana for PPC, Addition of fly ash significantly

improves the quality and durability characteristics of resulting concrete.

High volume fly ash concrete High volume fly ash concrete develops

sufficient early strength and workability, in addition to low temperature rise and

high ultimate strength. This is possible due to high dosage of plasticizer and low

W/C ratio to the extent of 0.30-0.35, ratio of cement, fly ash, fine and coarse

aggregates-1:1.75:3.5 with compressive strength reaching 40-45Mpa on the 90th

day.

3.8.3 Fly ash based innovative and commonly produced building products in India

Cellular light weight concrete blocks

33

CLC (Cellular light weight concrete) blocks are substitute to bricks and

conventional concrete blocks in building with density varying from 800 kg/m3 to

1800 kg/m3, The normal constituents of this are foaming agent based technology

cement, fly ash (to the extent 1/4"1 to 1/3

r" of total materials constituent), sand,

water and foam (generated from biodegradable foaming agent). Using CLC

walling and roofing panels can also be produced.

Advantages of CLC

Better strength to weight ratio

Reduction of dead load resulting in saving of steel and cement and

reduction in foundation size

Better acoustics and thermal insulation (air conditioning requirement is

considerably reduced)

Saving in consumption of mortar and higher fire rating

Development of fly ash based polymer composites as wood substitute

Fly ash based composites have been developed using fly ash as filler and

jute cloth as reinforcement. After treatment, the jute cloth is passed into the

matrix for lamination. The laminates are cured at specific temperature and

pressure,

Numbers of laminates are used for required thickness. The technology on

fly ash polymer composite using jute cloth as reinforcement for wood substitute

material can be applied in many applications like door shutters, partition panels,

flooring tiles, wall paneling, ceiling, etc.

With regard to wood substitute products, it may be noted that the developed

components/materials are stronger, more durable, resistant to corrosion and

above all cost-effective as compared to the conventional material i.e. wood.

Ready mixed fly ash concrete

Though ready mix concrete is quite popular in developed countries but in India it

consumes less than five per cent of total cement consumption. Only recently its

application has started growing at a faster rate. On an average, 20% fly ash (of

cement material) in the country is being used which can easily go very high. In

34

ready mix concrete, various ingredients and quality parameters are strictly

maintained/controlled which is not possible in the concrete produced at site and

hence it can accommodate still higher quantity of fly ash.

Fly-ash-sand-lime-gypsum (cement) bricks/blocks

Fly ash can be used in the range of 40-70%. The other ingredients are lime,

gypsum (cement), sand, stone dust/chips etc. Minimum compressive strength

(28 days) of 70 kg/cm2 can easily be achieved and this can go upto 250 kg/cm

2

(in autoclaved type).

Advantage of these bricks over burnt clay bricks

Lower requirement of mortar in construction

Plastering over brick can be avoided

Controlled dimensions, edges, smooth and fine finish and can be in

different colors (using pigments)

Cost-effective, energy-efficient and environment friendly (as avoids the use

of fertile clay)

Clay-fly ash bricks, Fly ash content can be 20%-60% depending on the

quality of clay. Process of manufacturing is same as for the burnt clay bricks.

Fuel requirement is considerably reduced as fly ash contains some

percentage of unburnt carbon

Better thermal insulation

Cost effective and environment friendly

3.8.4 Application of fly ash

Reinforced concrete (RC) (including ready mix concrete) to make use of fly

ash by using PPC containing fly ash. (Minimum 15% replacement of cement

with fly ash in PPC (Portland Pozzolona Cement) by weight of the cement used

in the overall RC for meeting the equivalent strength requirements).

Use fly-ash in building blocks for the wall. Use of fly ash- based

bricks/blocks (for e.g., Fal-G stabilized, fly ash-sand lime bricks, load bearing

and non-load bearing fly ash- based concrete blocks, fly ash- based light weight

aerated concrete walling blocks etc.) in case of both load- bearing and non-load

35

bearing wall systems, which utilize a minimum 40% of fly ash by weight of

cement for 100% load bearing and non-load bearing walls.

Use fly ash in Plaster/masonry mortar by employing PPC. Use plaster

and/or masonry mortar, which utilizes a minimum 30% of fly ash in PPC, in

100% wall/ceiling finishes and wall construction, meeting the required

structural properties.

3.9 Use low energy material in interiors

3.9.1 Objective

To use low-energy/recycled materials/finishes/products in the interiors, which

minimize the use of wood as a natural resource, and use low-energy materials

and products, such as composite wood products/rapidly renewable materials/

reused wood/low embodied energy products/products which utilize industrial

waste/ recycled products.

The various interior finishes used in the sub-system of the building or the

interior, which serve the aim of the credit, have been divided into the following

three major categories.

-assembly/internal partitions/Interior wood finishes/paneling/false

ceiling/In-built furniture/cabinetry

Flooring

Doors/windows, frames

3.10 Renewable energy utilization

3.10.1 Objective

To use of renewable energy sources in buildings to reduce the use of

conventional /fossil fuel- based energy resources

3.10.2 Use of renewable energy sources

36

Renewable sources of energy (such as solar, wind, biomass, geothermal, etc.)

can provide the energy required for meeting the building energy demand.

These sources are environmentally clean and non-exhaustible. Natural sources

of energy such as solar, wind, hydro power, tidal energy, ocean thermal and

hydrogen are all renewable energy sources. Projected availability of fossil fuels

in future and environmental degradation (including global warming) associated

with usage of these fuels are the driving forces for increasing use of renewable

energy sources.

3.10.3 Various renewable energy technologies

Power Generation Technologies

Wind Power

Small Hydro Power

Biomass Energy and Cogeneration

Biomass power

Biomass Cogeneration

Bagasse Cogeneration

Biomass gasification

Energy from Waste

Solar Energy Technologies

Solar Thermal

Solar water heating

Solar air drying

Solar cooker

Solar Photovoltaic

Solar home lighting

Solar Photo Voltaic water pumping

Solar lantern

Rural Energy Technologies

Biogas

Improved Chulhas

New Technologies

Fuel Cells

Hydrogen Energy

37

Geothermal

Ocean Energy

Tidal Energy

Ethanol

Biodiesel

3.10.4 Commitment

Energy requirement for a minimum 10% of internal lighting load (for general

lighting) or its equivalent is met from renewable energy sources (solar, wind,

biomass, fuel cells, etc.).

3.11 Renewable energy based hot water system

3.11.1 Objective

To use renewable energy sources to meet the hot -water need.

3.11.2 Guidelines for installation and use of solar systems

Solar collectors should face south for maximum solar radiation collection.

Solar collector tilt should be equal to the latitude of the place for maximum

annual energy collection.

Solar collector tilt equal to latitude + 150 gives maximum energy collection

in winter.

Solar collector tilt equal to latitude -150 gives maximum energy collection

in summer.

Always check load carrying capacity of the roof before placing the solar

system. Typically, each solar collector of 2 m2 area weighs 50 kg. The solar tank

when filled with water weighs 1.2–1.4 kg per litre capacity of tank. (For example,

100 litre capacity tank weighs 120 kg)

Ensure proper anchoring of the system duly considering wind conditions.

Solar collectors and tank must be easily accessible for cleaning and

maintenance.

38

Typically solar system needs 1.3–1.5 times the collector area for

installation. For example, a single collector system of 100 litre capacity having 2

m2 area needs 3 m2 of floor area for installation.

3.11.3 Guidelines for solar system selection and use

Check hardness of water to be used in solar system. Solar collectors have

small diameter pipes, which get chocked due to deposition of salt from hard water.

In case of hard water, either water softener or heat exchanger type solar water

heater can be used.

It is a good practice to consider solar system location and optimize the

associated hot/cold water piping layout during the building design stage to reduce

the cost and heat losses due to longer piping.

Always use good quality pipes and insulation for long life and trouble-free

working.

It‘s important to check operating pressure of supply of cold water line,

especially when pressurized water is circulated. Most solar systems available in

India are not designed for pressurized water supply.

Ensure continuous supply of water to the solar system for efficient and trouble-free

operations.

During long periods of no use (for example, while on vacation) always

cover the solar collectors with nontransparent covers (e.g. old bed sheet or jute

cloth)/to avoid overheating of solar system).

It is a good practice to use the entire hot water at a time.

Avoid using back up heater. Do not keep back-up heater switched on.

Set the thermostat of back-up heater at 55–600C.

Use proper vent or vacuum release valve and pressure relief valve for safe

operation of solar system.

Human body can tolerate temperature up to 450 C. Human skin burns at

water temperature above 550C. Storage water heater temperature can be set at

55+50C.

3.11.4 Guidelines for system sizing

Typically solar hot water system is sized to meet one day‘s requirement of

hot water during winter. Typical hot water consumptions for various activities are

39

given below. These can be used as guidelines for calculating total hot water

requirement. (The consumption figures may vary depending on life style, age,

habits, and weather conditions.)

For bathing using bucket water = 15 litre per person per day (one bucket).

For shower bath = 25 litre per person per day.

For bath tub = 35–50 litre per person per day.

For cooking = 5 litre per person per day.

For washing clothes = 10 litre per person per day.

For washing utensils etc. = 5 litre per person per meal.

For making tea/coffee = 150 ml per person per cup

3.11.5 Commitment

Ensure that a minimum 50% of the annual energy requirement for heating water

(for application such as hot water for all needs except for space heating, e.g. for

canteen, washing, bath rooms/toilets) is supplied from renewable energy sources.

3.12 Water recycle and reuse (including rainwater)

3.12.1 Objective

To utilize the treated waste water and rainwater for various applications (including

groundwater recharge) where potable municipal water is normally used to reduce

the load on both the municipal supplies as well as the sewerage system and to

improve the groundwater level

3.12.2 The basic concept of storage and recharging

The recharging or storing of water depends on the rainfall of a particular region,

and the sub-surface geology. In regions where the rainy season lasts for three to

four months, groundwater recharge is beneficial rather than storage, as the storage

cistern would remain empty during other parts of the year. In places where the

surface is impermeable and groundwater is saline or not of potable quality, it is not

advisable to go for groundwater recharging. Recharging can be done through

dugwells, borewells, recharge trenches, and recharge pits. Filter material at the

40

entry point is essential to maintain the quality of water. Settlement tank acts as a

buffer to hold the surplus water during the course of excess rainfall.

3.12.3 RAINWATER HARVESTING

"An Innovative Approach to Solve Water Crisis"

"Water is a strange natural resource. It can unite a community as easily as it can

divide it." 'Rainwater Harvesting' implies nothing but conservation of rainwater.

Rainwater Harvesting (RWH) is a tradition-renewed scientific technology applied

to augment the groundwater both quantitatively and qualitatively. Rain Water

Harvesting is a simple, economical but effective way to save rainwater for

consumption and artificial recharge to solve the water problem naturally.

India is one of the water rich countries of the World. The average annual

precipitation in India, 1150 mm, is higher than that of every other continent in the

world except South America (1596 mm) and twice that of the average annual

precipitation of the continent of Asia.

100 hours, in a year, when it falls on in those few hours, when the rivers and

streams swell up, then there is little water to capture to meet human needs.

Every time it rains, only about 5-20% of the total rain is recharged into the ground

depending upon the terrain, top soil condition, subsurface formation,

rainfall pattern, etc. The topsoil can hold only a fraction of water that falls on it and

the rest gradually percolates down, depending on the type of the soil and joins the

aquifers.

India is a water rich country

India is one of the nine countries which hold 90% of fresh water of the world

1. Brazil

2. The russian federation

3. Canada

4. Indonesia

5. China mainland

6. Columbia

7. Usa

41

8. Peru

9. India

Artificial recharge

Artificial recharge may be defined as the practice of increasing by artificial means,

the amount of water that enters the ground water reservoir. This is accomplished by

unique systems and techniques, depending on the site specifications.

How does a rainwater-harvesting system work?

A rainwater harvesting system runs on the principle of seepage of water into the

ground. Owing to various soil features, water from rainfall is often obstructed from

reaching an aquifer that is several metres underground. In the case of rainwater

harvesting, water infiltrates into an aquifer through an artificial recharge structure

and recharges the aquifer accordingly. Thus, rainwater falling on the surface has a

smooth passage to the aquifer, where it is stored; from there it can be retrieved for

future use. Certain places do not have natural aquifers. In such cases, it is possible

to construct artificial aquifers. These man-made aquifers are as effective as natural

ones for the purpose of storage and retrieval of water.

3.12.4 Commitment

Provide necessary treatment of waste water for achieving the desired

composition for various applications

Implement rainwater harvesting and storage systems depending on the

site-specific conditions.

Reuse the treated waste water and rainwater for meeting the building

water and irrigation demand.

Recharge the surplus water (after reuse) into the aquifer.

3.13 Use low -VOC paints/ adhesives/ sealants

42

3.13.1 Objective

Paints can have a major impact on the overall aesthetics of a space; sometimes

more than even flooring and furnishings because of the enormous square

footage coverage. Paints may also have a major negative impact on the indoor

air quality of a building, because they may contain chemicals called Volatile

organic compounds (VOCs) and other toxic components that evaporate into the

air and are harmful to the health of the occupants. VOCs are a primary

contributors to smog generation.

3.13.2 Environmental effects of paints

Paints have three major components: a pigment for color. A binder that holds

the pigment to the surface and a carrier or solvent (mineral spirits or water) to

dissolve and maintain the pigment. Latex, water based paints have significantly

lower environmental impacts than oil or solvent-based paints since they don‘t

use petroleum carriers or have nearly as many smog forming emissions.

According to the US Environment Protection Agency (USEPA), 9% of the

airborne pollutants creating ground level ozone come from the VOCs in paint.

Low and zero VOC paints have little or no smog-forming emissions.

3.13.3 Potential Health Effects of Paints

Paints is applied wet and must undergo a drying process, and sometimes a

chemical reaction, in order to form a solid paint film on the wall or other

surfaces. It is during this drying or chemical process that VOCs and other paint

component are released. Many paints contain a high percentage of VOCs so that

they will dry faster. Paints also continue to offgas somewhat for many days,

weeks, and months after application and especially each time the temperature

and humidity in the room rises

VOC refers to the class of chemicals which evaporate readily at room

temperature. They are in all oil-based paints as solvents. Many latex paints

(which use water as the ―solvent‖ or carrier) also contain VOCs as a part of

their paint chemistry. When these VOCs off gas, they may cause a variety of

43

health problems like nausea, dizziness, irritation of the eyes and respiratory tract

and more serious illness like heart, lung or kidney damage and cancer.

On air quality, they are excellent for use in buildings where it is desirable to

have very low levels of toxicity, such as hospitals, schools or the homes and

workspaces.

Once airborne, many VOCs have the ability to combine with each other, or with

other molecules in the air, to create new chemical compounds. Air quality

testing shows that indoor VOC levels are considerably ten times higher than

outdoor levels, and can be as much as one thousand times higher after a new

coat of paint.

3.13.4 Benefits of Low VOC Paints

Environmental

VOCs react with sunlight and nitrogen oxide in the atmosphere to form ground

level ozone, a chemical that has a detrimental effect on human health,

agricultural crops, forests and ecosystems. These problems can be eliminated

using low VOC paints

Economic

Healthy occupants are more productive and have less illness related

absenteeism. Use of high VOC content material can cause illness and may

decrease occupant productivity. These problems result in increased expenses

and liability for building owners, operators and insurance companies.

Indoor Environment

Selecting materials that are low in VOC helps reduce sources of pollutants

during the construction process and in the finished building. Also low Voc

paints have little odour.

3.13.5 Making Good Choices

Sometimes simply washing walls and/or using a little touch-up paint can

make them appear new. When it is necessary to paint, use least toxic and low or

44

non VOC products, and water based paints. This will also eliminate the need for

toxic solvents for clean up.

Remember that a more durable paint is less expensive in the long run. A

10 year paint may cost a little more than a 5 year, but there is only a one time

labor cost, which is the most expensive part of most paint jobs.

Proper preparation is also critical for a durable paint application. All

surface must be clean and dust free, with any visible cracking, peeling, or

blistering removed.

If there is existing paint, determine what it is and appropriately prepare

for the next coat. Be sure to choose primers and top coats that are compatible.

3.14 Minimize ozone depleting substances

3.14.1 Objective

Eliminate or control the release of ozone- depleting substances into the

atmosphere. The ozone depleting materials commonly used in buildings are

CFCs (chlorofluorocarbons) or HCFCs (hydro chlorofluorocarbons) in

refrigeration and air- conditioning systems, insulation, and halons in fire

suppression systems and extinguishers.

Substances containing Chlorine (or Bromine) contribute to the breakdown of

the ozone layer in the stratosphere, resulting in harmful ultra violet radiation

reaching earth's surface, and thus global climate change. Such substances are

mainly used in refrigerating and air-conditioning equipment, fire suppression

systems and extinguishers, and in insulation, and this has been a growing cause

for concern. Therefore, continued efforts are being made globally (in the form

of International agreements) to minimize the use of ozone depleting substances,

and gradually to replace them with environmentally friendly substances.

Trichlorofluoromethane (R11) is used as reference for measuring the Ozone

45

Depleting Potential (ODP) of a substance. ODP of R11 is 1. Some of the

commonly used substances in refrigerating and air-conditioning equipment are

listed in the table below.

3.14.2 Commitment

Use insulation with zero -ODP (ozone depletion potential) such as

HCFCfree rigid foam insulation, mineral fibre cellulose insulation, glass

fibre, wood fibre board, cork wool, expanded (bead) polystyrene, recycled

newspaper and jute, cotton etc. Avoid materials that do not inherently have a

zero -ODP such as polyurethane foams, polyisocyanurates , etc.

Install CFC-free equipment used for refrigeration and air conditioning.

Install halon -free fire suppression systems and fire extinguishers in the

building.

46

CHAPTER 4

CASE STUDY

47

4.1 CASE STUDY – 1

Centre for Environmental Science and Engineering, IIT Kanpur.

5-star GRIHA rated Green Building at IIT Kanpur.

48

Green Features

Existing landscape and

vegetation is largely

protected.

The first floor of the building has been pushed inside to protect a tree

outside.

Water body is integrated

with design for optimal

microclimate.

An internal courtyard shaded by louvers is provided, so that to allow

free air movement.

49

Natural light and ventilation through skylights & ventilators in common

spaces.

Roof shaded by bamboo

trellis with green cover to cut

direct heat gain.

50

Large openings to maximize natural daylight into interiors.

Efficient glazing for openings

which minimize solar gains in

summer, heat loss in winter.

• HVAC system

Use of geothermal

energy for cooling

Efficient chillers

Lighting system

Lamps with luminous

efficacy – 75lm/w

Average LPD < 1 W/ft2

51

Aerators are used which

reduces the flow rate to

2ltrs/min.

Rain water from the building and

surrounding area collected and

routed through a sedimentation

tank to water body for AC

cooling.

Magic eye sensors reduces

water flow to 0.4 ltrs/flush.

Overflow is led to a

groundwater recharge pit.

Magic eye solenoid valves

are installed in taps.

52

100% of outdoor lighting demand

met by solar energy.

30% of internal lighting demand

met from photovoltaic panels.

100% of hot water building

requirement is met by solar system.

Solar water heater panels.

53

4.2 CASE STUDY – 2

ADMINISTRATIVE BUILDING, MOTILAL NEHRU NIT,

ALLAHABAD

54

Salient features

• G+3 storey

• 2 entrances

• Pathways – PCC Paving, Tiled paving

• Parking – Paved, unshaded

• Solar powered outdoor lights.

• In corridors, artificial lighting is required during daytime.

• Vertical movement – 2 stairs & 2 lifts.

• Toilets – 2 male ( 3urinals, 2wc, 2wb)

2 female (2wc, 2wb) on each floor.

Administrative staff at MNNIT Allahabad.

Administrative officers Deans Officers in charge

Director Planning and

development

Chief warden.

Registrar Academics Training and placement

Dy. Registrar ( accounts) Accounts Purchase

Dy. Registrar ( academics) Students affairs Student welfare centre.

Public Information

Officer

Research and

consultancy

Civil (M) academic

campus.

Chief Vigilance Officer. Faculty welfare. Civil (M) road maintenance

Medical officer Civil (M) officers colony

A.E. ( mechanical) Civil (M) hostel

A.E. (electrical) Time table

Executive officer (

director)

Chairperson – ICCM

Programmer Chairperson – BOG

Foreman Co-ordinator – design

centre.

55

Floor-wise distribution of areas of administrative block, MNNIT Allahabad.

Ground floor

• Accounts office (105m²)

• Public information centre (20m²)

• Civil maintenance (58.5m²)

• Chief proctor (33m²)

• Accounts officer (21m²)

• Main office (105m²)

• Chief warden (22m²)

• Dean (R & C)-22m²

• Dean (P & D) – 22m²

• Staff rooms – 2

• Staff office – 3 (52.5m²)

• Trophy room (30m²)

• Male toilets – 2 (2wc, 2wb, 3Urinals)

• Female toilets – 2 ( 2wc, 2wb)Toilet area – 60m²

• Storage space (45m²)

• Electric room (16m²)

• Services (16m²)

• Lifts - 2 (13.5m²)

First floor

• Board room (104.5m²)

• Director‘s office (54m²)

with attached

• Sitting room (20m²)

• Toilet (5.4m²)

• Store (15m²)

• PA room (37.5m²)

• PA staff (16m²)

• Pantry (9.6m²)

• Registrar with PA (50m²)

56

• Deputy registrar (20m²)

• Chairman‘s office with attached (37.35m²)

• Sitting (12.9m²)

• Toilet (3.75m²)

• Staff room (30m²)

• Office (17.3m²)

• Senate room (200.23m²)

• Male toilet – 2 (2wc,2wb,3Urinals)

• Female toilets – 2 (2wc, 2wb) Toilet area – 60m²

• Store room (9.6m²)

• Electric room (16m²)

• Services (16m²)

• Stairs – 2 (30m²)

• Lifts - 2 (13.5m²)

Second floor

• Talk show and media room (104.5m²)

• Equipment room (43.61m²)

• Lab (31.7m²)

• Placement cell (93m²)

• Industry interaction (104.5m²)

• Office of placement in charge (18m²)

• Toilet (3.75m²)

• Staff room (16.7m²)

• Alumni association (30m²)

• Offices – 5 (104.6m²)

• Meeting room (23m²)

• Change room – 2 (19m²)

• Male toilet – 2 (2wc,2wb,3Urinals)

• Female toilets – 2 (2wc, 2wb) Toilet area – 60m²

• Store room – 2 (19.2m²)

57

• Electric room (16m²)

• Services (16m²)

• Stairs – 2 (30m²)

• Lifts - 2 (13.5m²)

Third floor

• Conference room – 2 (197.7m²)

• Auditorium – 200 persons (200.23m²)

• Offices – 6 (136m²)

• Meeting rooms – 2 (50.9m²)

• Store room – 4 (45.6m²)

• Staff room (21m²)

• Male toilets – 2 (2wc, 2wb, 3urinals)

• Female toilets – 2 (2wc, 2wb) Toilet area – 60m²

• Electric room (16m²)

• AHU (38m²)

• Stairs – 2 (30m²)

• Lifts - 2 (13.5m²)

58

CHAPTER 5

SITE ANALYSES

59

ANALYSES.

Site and area statements.

Location of the site:

Figure 5.1 – Site location

The proposed site is on national highway 200, 22 km from the Raipur, at village

Bharenga. The national highway is along the northern boundary of the site. The

net area of the site is 55.52 ha., from which 1.8 ha. of land is selected for

developing administrative building of NIT Raipur.

Figure 5.2 - Site

The site is polygonal in plan measuring 137.2 acres. The site has been provided by

government to National Institute of Technology, Raipur to develop a new campus..

60

A 12 meter wide internal city road flanks the south-east boundaries of the site. The site

being contiguous to the already developed areas of the city, it would not be difficult to

introduce municipal services in the project area.

Topology:

The site is flat with gentle slope towards south.

Geology & Soil Characteristics:

The site has top strata of evenly deposited muroom followed by black cotton soil. The

soil comprises soft, expansive clay with some amount of organic content.

Climate:

Raipur is located on latitude 21014‘ & longitude 81

034‘ E & is at 296 meter above near

sea level. The major climate factors affecting the nature of built form are solar

radiation ambient temperature, relative humidity, prevailing wind and rainfall. The

overall climate of Raipur can be termed as hot dry.

Temperature:

The annual mean maximum temperature in May is 46.40C & the mean minimum

temperature in December is 13.20C.

Wind direction:

Predominant wind direction is south-west and post monsoon & winter direction is

north-east.

Humidity:

Relative humidity during monsoon season is above 75% and during winter season is

below 40%.

Rainfall:

The average annual rainfall in the area is generally around 1400 mm. Rains are

predominant during July & August. On an average there are 61 rainy days in a year.

The Raipur District receives 87.1% of the total rainfall from the southwest monsoon

61

during June to September. The winter – rainfall accounts for 9% of the total rainfall.

During the Monsoon the maximum rainfall occurs during the month of August where

mean monthly rainfall was recorded at 363.7 mm. In monsoon season, the mean annual

rainfall is 1332 mm.

62

CHAPTER 6

DESIGN APPROACH

63

The concept aims at developing plan form of a building to integrate the three basic

elements of climate i.e. light, air and water into the built environment. These three

elements of nature, upon their integration into the built form, have their functional as well

as aesthetical impact. Their functional role is much crucial in present situation as a modern

building is not only amongst the worst polluter of climate but also the largest consumer of

energy.

6.1 Intuitive approach - Intuitions are the thoughts and preferences that come to mind

quickly, in response to a particular prevailing condition, without much reflection upon the

mathematical data or analytical calculations. When designing a building, a designer does

not starts with all the analytical data that is available, but the designer follows some

intuitions to develop a form, best suited to the local climatic conditions, required spatial

organization, functional suitability, development of form and aesthetical appeal.

Chhattisgarh is a landlocked state at the heart of India, having ―hot dry and

composite‖ climatic conditions. The challenges in designing for hot dry and composite

climate are: — heat is welcome in winters but avoidable in summer; wind is welcome

during humid months but avoidable during winters and hot summers. The major factors

that affect a climate responsive design could be identified as –

1. Shape 2. Orientation

3. Heat 4. Air

5. Water 6. Light

Following is an example showing the application of above stated factors with intuitional

thumb-rules in developing a form for climate

responsive administrative building.

6.2 Shape – Shape of any building develops from

a base form. One basic criterion for selecting the

base form is surface area to volume ratio (s/v

ratio). It is based on the concept that different geometric shapes with same volume have

different surface areas. This ratio is particularly important in the cases where climatic

intervention is crucial factor in designing. The final building form evolves from this

conceptual base-form. A building form with low surface area to volume ratio gains lesser

S/V ratio – The Surface area to volume ratio is three dimensional form of perimeter to area ratio

and is an important factor in determining heat gain

and heat loss through building fabric

64

Figure 6.3 - Orientation

Figure 6.1- comparing the surface area

Minimum surface area reduces heat transfer Increased surface area greater heat transfer

heat during summers and daytime and similarly loses lesser heat during winters and night.

Low s/v ratio is considered optimal for hot dry and composite climates as it reduces the

heat gain and heat loss, which in turn reduces the cooling and heating load of building

(Givoni, 1994). The s/v ratio indicates thermal performance of basic shapes rather than

complex ones. The most compact orthogonal building would be a cube (Fig.-6.1). But for

day lighting and ventilation, large areas exposed to external surfaces are considered good

(Behsh, 2001). Hence cube is elongated to increase its surface area and form a cuboid,

which is a rectangle in plan (Fig.-6.2). The compromise made with the thermal

performance of the external envelop can be compensated by using insulating material in

external fabric. The efficiency achieved through proper day lighting and ventilation by

increased surface area is an additional advantage. The thermal performance could be

adjusted by proper orientation of building block.

6.3 Orientation – After deciding the base form, the next step is to orient the block. In

northern hemisphere, north facade of the building does not receive any direct solar

radiation, whereas southern façade receives direct radiation in winter but very little in

summer. Also day light received from north is considered best as light from north is

diffused light which lacks glare. Hence longer façade should be oriented towards north—

south (Fig.-6.3). East and west walls receive maximum solar radiation, especially when the

sun is low in altitude. Solar gain on west and south-west part can be particularly

troublesome as its maximum intensity coincides with hottest part of the day (Brown,

2001). Therefore, shorter facade of the building shall face east—west direction.

Figure 6.2- basic plan

shape

S

E

W

N

S

E

W

N

65

Figure 4 - Courtyard

Figure 6.5 – Dividing the basic shape into four corner blocks

To assimilate the climate into the built environment, it is imperative to bring the light, air

and water into the building so that inhabitants get to feel these elements not only from

external facades but also from inside the building. Courtyard (Fig.-6.4) not only brings the

natural environment inside but also controls the internal environment and serves the need

of the inhabitants. It functions as a convective thermostat and gives protection from

extreme effects of hot summers and cold winters. It also creates moods with varying

degree of lights and shades and with them the ambience of abode.

Now, there is a rectangular block facing north-south, with central opening i.e. courtyard.

To incorporate light, air and water, it is required to further develop the plan form. Firstly,

dividing the existing block into four smaller blocks and modifying each block in such a

way so as the modified form of each block serves a specific purpose (Fig.-5).

Objectives for further modification of each block are-

1) To minimize solar radiation.

2) To bring air into building and allow it to pass through the fabric, preferably after

humidification.

3) To place a water body in windward side, so that it serves functionally and helps in

convective cooling of the building.

4) To bring in maximum north light into work areas.

6.4 Heat – Solar radiations from west and south-west direction is most uncomfortable and

troublesome as the radiation intensity from these directions is maximum when the day is

most heated. To minimize these radiations, north western block is removed and south-

western block is inclined with shorter façade facing south west (Fig.-6). As a result, only

S

E

W

N

S

E

W

N

66

Figure 6.6- Inclining south-western block and removing north-western block to

minimize heat gain.

small surface receives direct radiation and remaining faces receives lesser radiation. This

further reduces the heat gain into the building. Smaller face that receives direct radiation

can be insulated using hollow blocks or cavity walls with additional screen walls. Besides,

these spaces can be used for non conditioned uses as toilets, stairs, stores etc. that act as

buffer between habitable areas and uninhabitable areas.

6.5 Air – Air movement is a crucial factor for human comfort. To bring the air into the

structure, the most important thing is to know the prevailing wind direction for the local

area, which, in case of Raipur, is from south-west (Fig.-6.7). To use this wind, providing

an opening in the southern facade is not enough. Along with the south western block, that

deflects the air towards the building, a protrusion of south-eastern block is required to trap

this air. This creates a funnel with wide mouth inviting huge volume of air and narrow rear

end — pressurizing the air captured, thereby creating a high pressure zone. The courtyard,

being under low pressure, attracts the pressurized air, which ventilates the premises by

Venturi effect. To allow cross ventilation, a gap between northern and eastern block is left

(Fig.-6.8).

S

E

W

N

VENTURI EFFECT – Venturi effect occurs when

two building blocks are placed at an angle to each

other creating a funnel with narrow opening.

Wind channeling through the opening are

accelerated to high speed.

67

Figure 6.7 – Prevailing wind

direction from south-west.

Figure 6.8 – Adding and subtracting masses to catch

wind.

Figure 6.9 – Adding water body to south-west.

Figure 6.10 – Section showing air movement

through stilted block

6.6 Water- Aesthetically, water anywhere around the building or all around the building

looks visually pleasing. But from functional point of view in hot-dry and composite

climate, its placement becomes crucial. In case of Raipur, the wind coming from south-

west is mostly hot and dry and south west portion is also most heated part of the building.

Therefore, south-west corner is correct location for placing any water body (Fig-6.9). This

water keeps evaporating, cools and humidifies the in-flowing hot dry wind, before it enters

the confinements of the structure. South western block could be stilted to stretch water

body into the courtyard and also allow air to pass through from under the stilted block

(Fig-6.10).

6.7 Light – Most favorable natural light for better working condition in interiors is

diffused north light (Lechner, 2009). Providing longer north facade and courtyard at centre

allows ample daylight from both, exterior façade as well as interior courtyard facing

facades. For maximum north light, northern and eastern blocks are provided with openings

on north face. These blocks can be the most occupied work area as these are least heated

blocks with maximum north exposure. Northern facade is further modified form being

straight to ‗U‘ shaped, resulting in increased available window area (fig.-6.11).

S

E

W

N

Courtyard

Wind flow

Stilted south-west block

Water body

68

Figure 6.11 – Modifying Northern and Eastern blocks, to harness north light

Figure 6.12 – ‗U‘ shaped northern blocks, different shapes on each floor

Additionally shape of northern blocks on each floor is kept different which allows creating

voids in façade, allowing for cross ventilation and penetration of north light into internal

corridors (fig.-6.12).

Eastern blocks are modified as north-south oriented linear blocks, placed behind each other

at different levels, southern block being highest. This provides longer northern facades to

all blocks for light and placing them on levels ensures ample light even to the lowest floor

of southernmost block (fig.-13).

Figure 6.13 - Eastern blocks, height increasing backwards

S

E

W

N

69

Figure 6.14 – Conceptual view from North-East

corner

Figure 6.15 – Conceptual view from South-East

corner

6.8 Miscellaneous – Some additional measures, like concept of mutual shadowing is

applied on south western blocks. It can be done by sub dividing south western block into

smaller blocks and orienting them in such a way so as shadow of one falls on the other.

This further helps in reducing the surface area exposed to direct solar radiation. Open

courtyard at centre can be partially sheltered by bamboo trellis that allows filtered light to

pass through.

Intuitively, a form catering to a specific climatic need can be developed using some basic

guidelines. Step by step development of form tells about ‗how to do.‘ Next step would be

to find out ‗how much to do‘, i.e. analytical methods. Calculations will require local data

of solar angles, wind direction, wind speed, rainfall, shapes and sizes of openings and

fenestrations. There are simulative tools available to analyze the achieved thermal

performance of the building. This allows further modifying and fine tuning the design to

achieve desired comfort levels. Similar tools for calculating day light integration into the

building are also available. If initial intuitive approach for development of form is proper,

implementation of analytical data into the design becomes easier and asks for lesser

modifications on the form initially developed.

70

CHAPTER 7

SPECIAL STUDIES

71

7.1 ORIENTATION

In solar passive buildings, orientation is a major design consideration, mainly

with regard to solar radiation, daylight and wind. The orientation of the building should

be based on whether cooling or heating is predominant requirement in the building.

The amount of solar radiation falling on a surface varies with orientation. In tropical

climate zones for example, North Orientation receives solar radiation for a very brief

time period, and the intensity of radiation is minimum. Thus in tropical climate like

India long facades of buildings oriented towards north— south are preferred. East and

West receive maximum solar radiation during summer. South orientation receives

maximum solar radiation during winters. Orientation also plays an important role with

respect to wind direction. At building level, orientation affects the heat gain through

building envelope and thus the cooling demand, orientation may affect the daylight

factor depending upon the surrounding built forms, and finally the depending upon the

windward and leeward orientation fenestration could be designed to integrate natural

ventilation.

Electric lighting and mechanical air-conditioning for cooling are the largest energy

consumers in commercial buildings with high internal loads. Where site conditions

permit,\landscaping or other shade structures to reduce the amount of sun on the

building is the most effective method of solar control. Peak solar cooling loads are

greatest through southwest- and west-facing windows and walls; solar loads from

windows and walls facing other directions are smaller and easier to control. It is

important to evaluate the shading opportunities of existing and future buildings on

neighboring lots.

Where site conditions permit:

•Locate the building toward the southwest, south, or west sides of the site to

provide shade for lower floors from neighboring buildings.

•Orient the building with the short wall facing west or southwest for the least

solar gain in the summer.

•Place service cores or opaque stairwells at the southwest or west ends to buffer

interior spaces from afternoon solar gain.

72

•Orient the building with the long side east-west for highest winter gains and

lowest summer gains. Southeast or southwest orientation can capitalize on

morning or afternoon solar gains respectively without major losses in

performance.

7.2 DAY LIGHTING

Day lighting has a major effect on the appearance of space and can have

considerable energy-efficiency implications, if used properly. Its variability and

subtlety is pleasing to the occupants in contrast to the relatively monotonous

environment produced by artificial light. It helps to create optimum working

conditions by bringing out the natural contrast and colour of objects. The

presence of natural light can bring a sense of well being and awareness of the

wider environment. Daylighting is important particularly in commercial and

other non-domestic buildings that function during the day. Integration of

daylighting with artificial lighting brings about considerable savings in energy

consumption. A good daylighting system has a number of elements, most of

which must be incorporated into the building design at an early stage. This can

be achieved by considering the following in relation to the incidence of daylight

on the building.

■ Orientation, space organization, and geometry of the space to be lit

■ Location, form, and dimensions of the fenestrations through which day- light will

enter

■ Location and surface properties of internal partitions that affect daylight distribution

by reflection

■ Location, form, and dimensions of shading devices that provide protection from

excessive light and glare

■ Light and thermal characteristics of the glazing materials. Daylight integration is an

important aspect of energy-efficient building design, and most of the case studies

covered in this book have innovative daylighting strategies.

■ Floor plans with relatively narrow wings, ensure that most interior spaces have good

access to natural light and winds.

73

■ Redirecting daylight with light shelves, prismatic glazing and other reflective

systems can extend naturally lit interior space upto 10 mtrs. Deep.

■ Limit the maximum distance of workstations from the building exterior to 6-7 mtrs.

To ensure good views to most of the occupants

■ Useful daylight from typical windows can only reach 6-7 mtrs. Into spaces with

3mtrs. Floor to ceiling heights, floor plans deeper than ~ 15 mtrs. Will require constant

electric lighting.

7.3 SHADING DEVICES:-

Effect of angle of incidence

To simplify the lengthy calculation, the concept of solar gain factor (@)has

been introduced which expresses the proportion of the total heat admitted by a

window by whatever means.the value of this for different angle of incidence can

be read from graph given and the total incidence is to be multiplied by this

single value

External shading devices

Figure 7.1 External shading devices

Solar azimuth and altitude

The position of the sun is generally given as an azimuth and altitude angle:

74

Azimuth represents the horizontal angle of the sun relative to true north. This

angle is always positive in a clockwise direction from north when viewed from

above, and is usually given in the range 180Ñ° < azi < 180°.

Altitude represents the vertical angle the sun makes with the horizontal ground

plane. It is given as an angle in the range 0Ñ° < alt < 90°.

Figure 7.2 - Sun position in the sky is typically given as an azimuth and altitude angle.

The sun paths at various dates are shown by group of curves extending from

east to west (the date lines) which are intersected by short hour lines. The series

of concentric circle establish a scale of altitude angles and the perimeter scale

give the azimuth angle. From these two angle the sun position to the wall

surface of any orientation (thus the angle of incidence) can be established.

Angle of incidence

THE HORIZONTAL COMPONENT OF THE ANGLE OF INCIDENCE (§) will be the

difference between the solar azimuth and wall azimuth if ,the wall is facing

west (270) § =270- solar azimuth

The vertical component is the same as the solar altitude angle itself(y)

The angle of incidence (β)i.e. the angle between a line perpendicular to the wall

and the sun direction. Can be found bye the spherical cosine equation

cos β = cos § x cos y

Shadow angles

75

Shadow angles can be calculated for any time if the azimuth and altitude of the

sun are known.

Horizontal shadow angle (hsa)( §)

charectrises a vertical shading device andit is the difference between the solar

azimuth and wall azimuth ,same the horizontal component for the angel of

incidence.

Figure – 7.3 Horizontal shadow angle

Vertical Shadow Angle (VSA) (є)

Characterizes horizontal shading device a long horizontal projection from wall,

and it is measured on a vertical plane normal to the elevation considered

The distinction between solar altitude angle(y)and vertical shadow angel must

be clearly understood . the first describe the sun position in relation to the

horizon, the second describe the performance of the shading device

.numerically the two coincide (y = є) when ,and only when, the sun is exactly

opposite the wall considered(i.e. that when solar azimuth and wall azimuth

angel(ω) are the same when α= w)when the azimuth difference § =0 for all

other cases ,that is when the sun is sideways from the perpendicular the vertical

shadow angel is always larger than the solar altitude angel for which it would be

still effective є < y the relationships expressed as

Tan є = tan y x sec §

tan VSA= (tan (altitude) X sec (HSA))

76

Shade Dimensions

These two angles, HSA and VSA, can then be used to determine the size of the

shading device required for a window. If the height value refers to the vertical

distance between the shade and the window sill, then the depth of the shade and

its width from each side of the window can be determined using relatively

simple trigonometry.

Shade Depth

The depth of the shade is given by: depth(d) = height (h) / tan (VSA)

The width is given by: width (w) = depth (d) X tan(HSA)

The width simply refers to the additional projection from the side of the

window. Exactly which side is a matter of the time of day and which side of the

window the sun is on.

Rules of the thumb

The table below indicates the most appropriate type of shading device to

use for each orientation in the northern hemisphere. These are guidelines and, of

course, there are many variations to these basic types.

Orientation Effective shading

North (pole- facing) Fixed horizontal device

East or West Vertical device/louvers (moveable)

South (equator-

facing)

Fixed horizontal device

A window facing south direction should be shaded with a horizontal shading

device and any vertical device is preferred in low altitude sun to give

appropriate horizontal shadow angle. Whereas, it is preferred a long horizontal

projection or vertical shading device in west and east directions.

77

7.4 PASSIVE COOLING OF BUILDINGS

Cooling of building by passive system can be provided through the utilization

of several natural heat sink : the ambient air , the upper atmosphere, and the

under surface soil. Such cooling system include:

Comfort ventilation: Providing direct human comfort by natural

ventilation, mainly during day time hours.

Nocturnal ventilative cooling: Lowering the indoor day time

temperature by ventilating the building at night.

Radiant cooling: utilizing the process of nocturnal long wave radiation

to the sky.

Indirect: Evaporating cooling of the building by roof ponds and wetted

conductive impermeable walls.

Soil cooling: Utilizing the soil as a cooling source for building.

Ventilation requirements

Ventilation has three function, which require different level of airflow through

the building:

1. Maintaining acceptable indoor quality by replacing indoor air, vitiated in

the processes of living and occupancy ,with fresh outdoor air. This function

of ventilation is needed in all climate but is of intrest mainly in cold

climates, and also in air conditioned buildings in all climate type.

2. Providing thermal comfort in warm environment by increasing

convective heat loss from body and preventing discomfort from excessively

moist skinthrough higher airspeed over the body (discomfort ventilation).

3. Cooling the structural mass of the building during the night and utilizing

the cooled mass as a heat ―sink ― during the following daytime hours in

order to maintain the indoor temperature well below the outdoor

level(nocturnal ventilative cooling.)

The physical forces generating ventilation

78

Ventilation, mainly the flow of outdoor air through a building, occurs when

opening are available at point exposed to different levels of air pressure. Such

pressure gradient (or pressure heads) can be generated by two forces:

(a) Temperature difference between indoors and outdoor (thermal ,or

thermosyphonic force)

(b) Wind flow against the building (wind pressure force)

Features affecting ventilation

The main design features which affect the indoor ventilation conditions are

Type of building

Orientation of the building, especially the openings, with respect to wind

direction.

Total area of opening in the pressure and suction region of the building‘s

Envelop.

Type of window and detail of their opening.

Vertical location of opening.

Interior obstructions to airflow from the Inlet to the outlet openings.

Specialized details which direct the air into the building.

Direct Gain - Cooling Cycle

It is vital to provide cross-ventilation in a building in summer to not only supply

fresh air but also:

Give instantaneous cooling whenever the inside temperature is higher

than the outside one;

Remove overnight the heat stored in the building fabric during the day

commonly referred to as night purging; and

Provide the feeling of cooling on the skin by accelerating its evaporative

cooling (this can also be provided by the use of fans, particularly ceiling

fans)

79

Solar shading should be configured over the northern windows to exclude

access to most summer sun to the interior spaces. Additionally, it is desirable to

provide extra shading by a pergola planted with deciduous vines, or adjustable

(fabric or metal) blinds on the northern windows to protect them from heat gain

in unseasonably hot weather occurring in early autumn or late spring. As the

outside air temperature increases during a summer day the inside air

temperature is modified by the walls and floor absorbing heat from the air.

Additional efficiencies can be introduced into the direct-gain cooling cycle by:

Fostering vegetation near the southern-side openings used for ventilation

- if these plants are watered in summer the air passing through them will be

partly cooled before entering the internal space;

Planting deciduous trees or vines on the northern and western sides of a

building to provide shade in summer and admit sunlight in winter;

In sub-tropical and tropical humid zones and in humid areas of other

zones, adopting a design with a ventilated space between the roofing and the

ceiling;

Adding suitable insulation under the roofing material.

Table 7.1- R and C values of different materials

80

7.4 BUILDING MATERIALS

Buildings consume vast amounts of our resources and threaten the

ecological systems that support life, from the ozone layer to the world's

forests. Changing the way we build has become imperative. Manufacturing

the cement for the 55 yards of concrete 'm the foundation generates on the

order of 20,000 Ibs. of C02 emissions. Commercial buildings are resource-

intensive to build. Over their operating lives, most buildings consume many

times the energy used during [[construction

Using the most environmentally sound materials is an important step in

the overall goal of improving the environmental performance of any

building.

The building industry is beginning to respond to these concerns. New

products .and materials are being developed that use resources more

efficiently. Manufacturing processes have started to be redesigned/upgraded

to reduce waste and pollution.

New and old products made from recycled materials are available, but

these have to be furthered. Concern over toxins entering the environment is

being reflected in less toxic materials.

Construction methods have to be developed to increase efficiency and

reduce job-site waste. In some areas where the industry has evolved over

the past few years energy efficiency standards have increased. But still lot

of areas are still not evolved. It has to be even/ones continuous effort in

struggle to save the planet by making sustainable developments.

One of the paths will be to become more and more selective and

resource efficient in future in terms of the materials that we use -materials

that are renewable, biodegradable, have low in embodies energy, and

locally produced will further this green movement

Environmental Criteria

For evaluating any material the environmental impact of the material has to be

considered for the complete life cycle of the material including harvesting,

manufacturing, distribution, installation, operations, reuse, or disposal.

81

The Challenges in defining ‘what is Green?’

Many of these criteria used to select products are, by nature, subjective, and a product

may perform well under one criteria but poorly under another. Tradeoffs between

different criteria are inevitable.

Frequently these criteria are in conflict. For example, engineered wood products use

trees more efficiently than sawn lumber, but they also contain a lot of glue and resins

that can create indoor air quality problems and make the products harder to recycle.

Concrete is extremely durable and can provide energy saving thermal mass, but the

production of cement is energy-intensive and contributes significant amounts of carbon

dioxide to the atmosphere.

The standards and thresholds by which we weigh now, have to evolve and

continuously get upgraded over time.

Even in the greenest of projects it is likely that many products will be used that are not

themselves green - but they are used in a manner that helps reduce the overall

environmental impacts of the building. A particular window may not be green, but the

way it is used maximizes collection of low winter sunlight and blocks the summer sun.

So even a relatively conventional window can help make a house green. Creating a

green building means matching the products and materials to the specific design

and site to minimize the overall environmental impact.

Green products in isolation hold not much value, as Green products could be used in

bad, non judicious ways that result in buildings that are far from environmentally

responsible. In a well-though-out building design, however, substituting green products

for conventional products can make the difference between a good building and great

one.

Source of Material

a. Renewable source–Rapidly renewable sources e.g. wood from certified

forests

b. Reuse of Waste-Salvaged products –e.g. old plumbing, door frames

c. Recycled contents –agriculture/ industrial waste e.g. Bagasse Board

82

Embodied Energy

Scalar total of energy input required to produce the product including

transporting them to the building site

Figure 7.4 – Embodied energy of different materials

Local Availability

Transportation Cost–For materials not available locally the transportation cost

can form a significant part of its embodied energy.

Reduce Pollution

Air Pollution-Use of materials with low VOC emissions e.g. Cement

Paints

Land Pollution-Materials that reuse waste that would otherwise have

resulted in landfill. e.g. Flyash Bricks

Water Pollution–Materials that prevent leaching.

Performance

Durability & Life Span-Material that are exceptionally durable, or

require low maintenance e.g PVC pipes.

Reduce material use-These are energy efficient and also help reduce the

dead load of a building. e.g. Ferrocement

Energy Conservation

Materials that require less energy during construction e.g. precast slabs

83

Products that conserve energy–e. g. CFL lamps.

Materials that help reduce the cooling loads-e.g –aerated concrete

blocks.

Fixtures & equipments that help conserve water e.g. Dual flush cisterns

Recyclable

Reuse or Recycle as different product e.g. steel, aluminum.

Biodegradable –that decompose easily e.g wood or earthen materials.

Recommended alternatives

Roofing and ceiling-

Alternatives to Ferrous / non-ferrous sheets, tiles, thatch

a. Fibre Reinforced Polymer Plastics instead of PVC and Foam PVC,

Polycarbonates, acrylics & plastics

b. Micro Concrete Roofing Tiles

c. Bamboo Matt Corrugated Roofing Sheets

Tiles for interiors

a. Terrazzo floor for terraces and semi covered areas

b. Ceramic tiles (non-vitrified)

c. Mosaic Tiles/ Terrazzo Flooring

d. Cement Tiles

e. Phospho-Gypsum Tiles

f. Bamboo Board Flooring

Windows, Doors and openings –

Alternatives to Timber and Aluminum / Steel frames

a. Ferro cement

b. Pre-cast R.C.C. Frames/ Frameless Doors

c. Hollow recycled steel channels and recycled Aluminum Channels and

Components

Shutters and Panels –

Alternatives to timber, plywood, glass, aluminum

a. Red Mud based Composite door shutters,

84

b. Laminated Hollow Composite Shutters

c. Other wood alternatives

Wood

• Renewable timber from plantations or timber from a government

certified forest / plantation or timber from salvaged wood

• Plywood should be phenol bonded and not urea bonded

• Use of MDF Board

• Instead of Plywood: Bamboo Ply/Mat Board/ Fibre Reinforced Polymer

Board/ Bagasse Board /Coir Composite Board /Bamboo mat Veneer Composite.

• Use of Mica Laminates and Veneer on Composite boards instead of

natural timber.

85

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