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					                                    A FULL LENGTH PAPER



                                         ABSTRACT
                                            ON

                                     GREEN BUILDING

The Buildings are part of basic needs. It is for protecting us from Nature's extremes: cold, heat,
wind and Rain. But these structures affect and shape our environment too. Constructing and op-
erating buildings requires enormous amounts of energy, water, and materials and creates large
amounts of waste. Where and how they are built affects the ecosystems around us in countless
ways. And the buildings themselves create new indoor environments that present new environ-
mental problems and challenges.


                  As the environmental impact of buildings becomes more apparent, a new field
called green building is Arising to reduce that impact at the source. Green or sustainable building
is the practice of creating healthier and more resource-efficient models of construction, renova-
tion, operation, maintenance, and demolition.


                  This paper discusses the design and operating the buildings to use energy effi-
ciently and
to use renewable sources of energy including solar and wind, reducing waste from construction,
design and operating the building to use water efficiently.


              Green building is a rational response to two driving forces – firstly, a new set of
resource constraints facing the globe and secondly, to a demand for healthier, more productive
environments for users. ―Green building is a natural evolution of the building sector, responding
to an emerging set of economic forces. It is not a passing fad, but the way things will have to be
done in future‖




                                                 1
                                             INDEX


1. GREEN BUILDING

2. OBJECTIVES OF GREEN BUILDINGS

3. BENEFITS OF GREEN BUILDINGS
     3.1 Environmental benefits
     3.2 Economic benefits
     3.3 Social benefits

4. CONSIDERATIONS OF A GREEN BUILDING
   4.1. Site considerations for green building

5. HOW TO MAKE A GREEN BUILDING?

6. BUILDING DESIGN
   6.1 Use efficient system and control

7. WHOLE DESIGN OF GREEN BUILDING

8. BUILDING ENVELOP IN GREEN BUILDING
   8.1Enclosure of a green home

9. COMFORTABLE IN GREEN HOME

10. DAYLIGHT AND ULTRAVIOLET RADIATION

11. ENERGY EFFICIENT GREEN HOME
    11.1 Heat flow and control in green building

12. HUMIDITY CONTROL IN GREEN BUILDING
    12.1 Ideal humidity
    12.2 Low humidity
    12.3 High humidity

13. INDOOR AIR QUALITY
    13.1. Indoor air pollutants and health
    13.2. Volatile organic compounds

14. MOISTURE CONTROL IN GREEN BUILDING

                                                   2
15. PASSIVE SOLAR DESIGN IN GREEN BUILDING


16. NOISE CONTROL IN GREEN BUILDING
    16.1 Important noise control in green building

17. EXTERIOR WATER CONSERVATION IN GREEN BUILDING
    17.1 Landscaping a green building
    17.2 Permeable or pervious paving in green building


18. INTERIOR WATER CONSERVATION IN GREEN BUILDING
    18.1 Saving water in a green home
    18.2 Hot water in a home
        18.2.1 Solar hot water
        18.2.2 Recirculating cold water
        18.2.3 on the way to the shower

19. INSULATION
20. MATERIAL
21. CONCLUSION




                                                 3
1. GREEN BUILDING: A green building, also known as a sustainable building, is a structure
that is designed, built, renovated, operated, or reused in an ecological and resource-efficient
manner.
         Sustainable development is maintaining a delicate balance between the human need to
improve lifestyles and feeling of well being on one hand, and preserving natural resources and
ecosystems, on which we and future generation depend.

2. OBJECTIVES OF GREEN BUILDINGS:

      Protecting occupant health.
      Improving employee productivity.
      Using energy, water and other resources more efficiently.
      Reducing overall impact to the environment.
      Optimal environmental and economic performance.
      Satisfying and quality indoor spaces.



3. BENEFITS OF GREEN BUILDINGS:




3.1 Environmental Benefits:

       Emissions Reduction. Pollutants released by fossil fuel fired electricity contribute to
       global climate change, cause air quality issues such as acid rain and smog, and pose risks


                                               4
      to human health. Green building techniques like solar powering, day lighting, and facili-
      tation of public transport increase energy efficiency and reduce harmful emissions.
      Water Conservation. Recycling rainwater and greywater for purposes like urinal flow
      and irrigation can preserve potable water and yield significant water savings.
      Storm water Management. Storm water runoff can cause waterway erosion, flooding,
      and carry pollutants into water sources. Harvesting and redirecting storm water, building
      surfaces with permeable materials, and using green roofs can control and utilize over-
      flow.
      Temperature Moderation. The heat retention properties of tall buildings and urban ma-
      terials such as concrete and asphalt are the primary causes of urban heat island effect.
      These conditions may be offset by conscientious building design and site selection, as
      well as planting trees to accompany new developments.
      Waste Reduction. Construction and demolition generates a huge portion of solid waste.
      Building deconstruction as an alternative to full-scale demolition results in massive de-
      creases of waste production.

3.2 Economic Benefits:

       A common impression about green building is that the green premium is too expensive
       to be considered economically feasible. However, studies have shown that the costs of
       green buildings are not substantially higher than regular development projects. Higher
       construction costs can generally be avoided by the inclusion of green design from the
       outset of the project. Additionally, green buildings provide an assortment of economic
       advantages.

       Energy and Water Savings. The resource efficiency provided by green design and
       technology leads to drastic reductions in operation costs that quickly recoup any addi-
       tional project costs and continue to offer dramatic long-term savings. Money previously
       directed toward utility costs may be used for other purposes.
       Increased Property Values. With energy costs on the rise, the low operating costs and
       easy maintenance of green buildings make for lower vacancy rates and higher property
       values.
       Decreased Infrastructure Strain. Efficient buildings exert less demand on the local
       power grid and water supply, stretching the capacity of local infrastructure.
       Improved Employee Attendance. Green design emphasizes increased natural lighting
       and control of ventilation and temperature-attributes that improve employee health and
       prevent absences.
       Increased Employee Productivity. Employee productivity has been positively corre-
       lated to indoor environmental conditions, and shows improvements where green prin-
       ciples have been applied.
       Sales Improvements. Studies show better sales in stores that utilize natural light. Re-
       tailers are increasingly using day lighting in an effort to harvest the associated sales ben-
       efits.
       Development of Local Talent Pool. With increased attention being paid to global cli-
       mate change and the need for renewable energy sources, the field of building design and
       construction is moving toward sustainability as a permanent objective designers and

                                                5
        builders experienced with green projects able to accommodate the growing market de-
        mand for sustainable development.

3.3 Social Benefits:

         Improved Health. Poor indoor environmental quality (IEQ) resulting from insufficient
         air circulation, poor lighting, mold build up, temperature variances, carpeting and furni-
         ture materials, pesticides, toxic adhesives and paints, and high concentration of pollu-
         tants (typically 10 to 100 times higher than outdoors) contribute widely to respiratory
         problems, allergies, nausea, headaches, and skin rashes. Green building emphasizes
         ventilation and non-toxic, low emitting materials that create healthier and more com-
         fortable living and working environments.
         Improved Schools. An estimated 40% of schools in the United States are subject to
         poor environmental conditions that compromise the health and learning of students.
         The healthier environment and atmosphere in school buildings utilizing green design
         and construction principles is shown to lead to significant reductions in student absen-
         teeism and improvements in test scores.
         Healthier Lifestyles and Recreation. A key element of sustainable design is the pre-
         servation of natural environments, which afford a variety of recreation and exercise op-
         portunities. Green buildings also seek to facilitate alternatives to driving, such as bi-
         cycling and public transport, which eases local traffic while encouraging personal
         health and fitness.

4. CONSIDERATIONS OF A GREEN BUILDING:

       Control erosion to reduce negative impacts on water and air quality.
       Reduce pollution and land development impacts from automobile use.
       Limit disruption of natural water hydrology by reducing impervious cover, increasing on-
       site infiltration and managing storm water run-off.
       Encourage and recognize increasing levels of self supply through renewable technologies
       to reduce environmental impacts associated with fossil fuel energy use.
       Provide a high level of individual occupant control of ventilation and lighting systems to
       support good health, better productivity and a comfortable atmosphere.
       Provide a connection between indoor spaces and outdoor environment through the intro-
       duction of sunlight and views into the occupied areas of the building.

4.1 Site considerations for green building:
"Site considerations" can include the location of the land, its relationship and proximity to exist-
ing developed land, previous uses of the land, as well as the orientation and design of the home
on the particular site. When more narrowly defined, site considerations includes simply the rela-
tionship of the specific home to the land it occupies—how the home is situated, how it's designed
and landscaped, and the green building products it contains to make the most of the surrounding
environment. Once the land for the home has been chosen, you'll need to analyze the site's par-
ticular characteristics to design and orient the home appropriately. Following are key environ-
mental elements of the site to consider and ideas for green building practices to make the home
and surrounding environment work in concert.

                                                 6
Climate:
Several climatic conditions must be considered and used to your advantage in designing and
placing a home on a site: solar access; air movement patterns; average temperature and rainfall;
microclimate factors, such as snow and wind load; and whether the site is in a predominantly
heating or predominantly cooling region. In mild climates, it makes sense to design outdoor
rooms, patios, and decks into the home to encourage homeowners to use outdoor spaces and pos-
sibly reduce the amount of indoor square footage that needs to be constructed, then heated and
cooled. Homeowners also can benefit from the psychological effects of being outdoors. Other
green building practices, such as passive solar heating, day lighting, and natural cooling from
operable windows and channeled breezes, can be incorporated cost-effectively into most homes.



Topography:
The site's topography is an important consideration in home placement. Topographical features
influence drainage and air movement. Also, placing the home on a relatively flat area and in a
natural clearing, as opposed to on a steep slope, will disrupt the natural vegetation less. When
building on steep slopes, it's difficult to avoid soil erosion, loss of hillside vegetation, growth of
invasive exotic vegetation, and damage to waterways. In addition, finding a flat area for the
home will be less expensive than building on a slope. Positioning the home to keep service lines
and roads as short as possible will leave the most pristine areas of the site untouched.

Also consider locating the home in view of natural topographic formations—rocks, trees, or hills.
These can make a home feel welcoming and sheltered, which may encourage homeowners to use
outdoor living spaces and reduce their square footage requirement of the home.

Water:
Study the site to understand the groundwater and surface runoff characteristics. Then, design the
home's landscaping to absorb storm water rather than construct expensive storm sewers to carry
rainwater offsite. To reduce or eliminate the need for additional landscape watering, select
drought-resistant native plants and perennial groundcovers. When landscape watering is neces-
sary, consider the site's natural water availability—the average annual precipitation—and use
rooftop water catchments to collect for outdoor watering.

Existing vegetation:
Consider carefully the site's existing vegetation and use it to the home's advantage. Are there any
natural clusters of trees that could be used for summer shading assistance? Or any natural shrub
formations that could help channel cool summer breezes into the home and block cold winter
winds? When necessary, consider relocating existing trees and other native vegetation to create
these effects. For example, adding trees on the east and west sides of the home can help shade
the home from early morning and late-day direct sun, dramatically reducing cooling loads. Creat-
ing hedge rows by relocating native plants can help block and channel airflow toward the home
as desired. Furthermore, relocating existing vegetation will save on the cost for new landscaping
plants, and it will require little or no watering. Be sensitive to any existing vegetation that is en-
dangered, and treat it accordingly.

                                                  7
Wildlife:
Avoid disrupting the wildlife as much as possible. Instead, find out about any animal migration
or mating areas on the site, and do not locate the home in close proximity. Respecting existing
wildlife trails and habitats preserves these areas for the animals and helps the homeowner avoid
wildlife nuisances. It also provides observation enjoyment for the homeowner, especially if the
home design includes large windows and outdoor living areas in view of wildlife habitat. Be sen-
sitive to any wetlands or endangered species of animals on the site and treat these accordingly.

5. HOW TO MAKE A BUILDING?

        Sustainable site planning with bioclimatic architectural planning
        Incorporate solar passive techniques in a building design to minimize load on conven-
        tional systems
        Design energy efficient lighting and HVAC (heating, ventilation, and air conditioning)
        system
        Use low energy and renewable materials
        Choose construction materials and interior finishes products with zero or low emissions
        to improve indoor air quality
        Use dimensional planning and other material efficiency strategies
        Design for a gray water system that recovers rain water for site irrigation and a dual
        plumbing system for use of recycled water for toilet flushing
        Use re-circulating systems for centralized hot water distribution.

6. BUILDING DESIGN: Design and construction practices that significantly reduce or elimi-
nate the negative impact of buildings on the environment and occupants in five broad areas:

       Sustainable site planning.
       Safeguarding water and water efficiency
       Energy efficiency and renewable energy
       Conservation of materials and resources
       Indoor environmental quality
       Building insulation

6.1 Use efficient systems and controls

       Lighting systems (CFLs, T-5 fluorescent lamps, LEDs, efficient ballasts, etc)
       HVAC systems (Properly sized plants, efficient chillers, VAV based air handling sys-
       tems, economizers, variable speed drives for pumps, chillers and fans etc.)
       Water heating systems (solar assisted water heating systems, efficient boilers etc)
       Energy management and control system




                                                 8
                     WHOLE BUILDING ENERGY OPTIMIZATION




7. WHOLE DESIGN OF GREEN BUILDING:

     Architectural design or site planning
     Lighting design
     Water system design
     Energy management and control design
     HVAC design


                                             9
 8. BUILDING ENVELOP IN GREEN BUILDING:

 8.1 ENCLOSURE OF A GREEN HOME:

 The elements of a home (including all external building materials, windows, and walls) that en-
 close the internal space are known as the building envelope, enclosure, or shell.
 The envelope serves as the outer armor to protect the indoor environment as well as to facilitate
 its climate control. It is that part of the home which physically separates the exterior environment
 from the interior environment. It prevents air, moisture and heat/cool from flowing freely in or
 out of the home and is crucial to the performance of the building.

 There are three parts to the building envelope. Although the parts are quite different from each
 other, they interact and comprise a physical system:

 1. Exterior Environments
 2. Interior Environments
 3. The Envelope System Itself
 This three-dimensional envelope starts with the inside face of the innermost interior layer, such
 as the interior paint, and extends to the face of the outermost layer, such as the exterior paint.
 The primary function of the home envelope is to separate the interior environment from exposure
 to the exterior environment. It is an assembly made up of all the adjacent enclosures.
 The components of the building envelope are:

.   The base floor systems
.   The above-grade wall systems
.   The windows and doors
.   The roof systems
 Borders defining where the exterior environment ends and the building envelope begins might be
 confusing, particularly when buffer spaces such as attics, garages, and crawlspaces are consi-
 dered.

 For a high-performing building, the envelope controls heat gain in summer and heat loss in win-
 ter. It should be equal in importance to the structural frame in terms of design consideration
 while taking properties of the envelope into account such as the function, position, dimensions
 and orientation.

 9.COMFORTABLE IN GREEN HOME: The basic reason people live in houses is to be more
 comfortable and safe than they would be outdoors; Houses buffer their inhabitants from weather
 extremes and keep them safe from animals, human or otherwise. Unfortunately, architects and
 home designers often created homes of beauty in the past, then "threw" enough energy at these
 homes to make them comfortable. Now that utility bills and climate change have entered the
 green equation, design principles must adjust to include both beauty and energy efficiency. Com-
 fort is not determined by temperature alone. Other conditions that affect comfort are:
          Humidity

                                                 10
       Air movement (breezes, fans, drafts)
       Temperature of surrounding surfaces (cold window, hot stove)
       Activity levels of people (reading vs. vacuuming)
       Different perceptions of what is comfortable.
Perception is important: Some are comfortable in summer at 80 degrees, others consider that
much too hot. Most people are comfortable and easily maintain their own internal temperatures
when temperatures around them are between 68 degrees and 80 degrees and when they are also:
  Sitting
  Lightly Clothed
  In still air
  In humidity of close to 50%
People also have slightly different perceptions of a comfortable daytime temperature as opposed
to a comfortable nighttime temperature.

10. DAY LIGHT AND ULTRAVIOLET RADIATION: All energies that move at the speed
of light are collectively referred to as electromagnetic radiation or "light."

Daylight
Most humans thrive in daylight. Incorporating this daylight into our green homes even has an
effect upon our psychological health and at times, even our soul. It is part of green building and
green living. The energy from the sun can either be harnessed for our use or be a cause of over-
heating in our homes. Unfortunately, it is most often a source of overheating in Dallas-Fort
Worth.

Ultraviolet Light
Various types of light differ in their wavelength, frequency and energy; higher energy waves
have higher frequencies and shorter wavelengths. Ultraviolet (UV) light is electromagnetic radia-
tion with a wavelength shorter than that of visible light. It has a shorter wavelength than that of
violet light, hence the "ultraviolet" name. It is also called "black light," as it is invisible to the
human eye. We need some ultraviolet radiation each day as UVB induces the production of Vi-
tamin D in the skin. Yet this light is a major source of material damage, both inside and outside
of the home, and must have consideration in green building.

Balancing Act
Because of overheating from the sun and the damage of UV light, there is a thin line for a green
builder to balance in North Central Texas. Green building balances between having enough day-
light to save electricity & soul, harnessing that energy for our benefit, and protecting our homes
from overheating most of the year and protecting humans and homes from the harmful effect of
UV radiation.

11. ENERGY EFFICIENT GREEN HOME: "A home can be energy-efficient without being
green. However, a home cannot be green without being energy efficient."Thus, an energy-
efficient home would be one that reduced energy input for the same service or gave an increased

                                                 11
 service or comfort for the same amount of energy. A green home, however, is one that is energy-
 efficient but also comfortable, durable, and healthy while using less natural resources and fewer
 toxic chemicals to construct

 11.1 Heat flow and control in green building: The control of heat flow into and within build-
 ings saves energy which saves money. It makes us comfortable. It impacts health, durability, and
 productivity. It helps to eliminate mold growth and interior condensation. It reduces the impact
 of our homes on the environment. Heat control is crucial to green building.
 The two most important sources of heat flow are heat from the sun, which creates passive solar
 design, and the movement of air. The natural tendency of heat is to move from warmer objects
 or spaces to cooler objects or spaces.
 Heat flows through buildings from:
.   Solar radiation through windows.
.   Objects in the building envelope other than windows.
.   Leakage.
.   Ventilation.
.   Generation of heat from animal or human bodies or through their activities such as washing
         clothes or
    Cooking.

 Controlling heat flow with as little energy expense as possible is an important aspect of design-
 ing green buildings. Yet, controlling heat in a building is complicated. It requires effective:
.   Air barriers
.   Control of solar radiation
.   Insulation
.   Control of heat generated internally
.   Control of thermal bridging.




                                                12
12. HUMIDITY CONTROL IN GREEN BUILDING: A comfortable home in the North Tex-
as area is certainly governed by temperature. But humidity plays a large role in comfort; particu-
larly during the summer. Humidity is the amount of water vapor in the air. It is measured in three
ways: absolute humidity, relative humidity, and specific humidity. See glossary
Humidity is increased or decreased by several mechanisms:
       Air pressure differences cause air to move from high to low pressure. Moving air can ei-
       ther bring
       Water vapor with it or take water vapor from the home.
       Humidity comes from many indoor activities such things as cooking, washing dishes,
       bathing, and doing laundry. Even human bodies increase the humidity in a home.
       Drafts can also affect the amount of humidity present so humidity problems are fairly
       common in
       Older or less energy-efficient homes.
       If the amount of water vapor in the air is held constant: 


       When you reduce the temperature, the relative humidity goes up.
       When you increase the temperature, the relative humidity goes down.

12.1 Ideal Humidity
Humans are very sensitive to humidity, as the skin relies on the air to get rid of moisture. The
ideal humidity level for homes is 45%.

12.2 Low Humidity
An indoor humidity level of less than 30% is too dry. You will know your home's humidity is too
low if static electricity is shocking you. Skin irritation and Respiratory problems are other signs
of low humidity. Low humidity dries out the noses and throats of the home's residents. It causes
scratchy dry throat, increased allergy symptoms, more frequent colds/infections, and even

                                                13
cracked fingers. It also affects the wood in the home, which shrinks, often damaging trim, hard-
wood flooring, and even wood furniture. Sheetrock and paneling may crack from low humidity.
A home's heating system will lower the humidity.

12.3 High Humidity
However, the reverse is true with a more energy-efficient home and a tighter envelope. The lack
of air exchange coupled with humans and their activities can cause high indoor humidity.

 13. INDOOR AIR QUALITY: Indoor air quality refers to the presence or absence of air pollu-
tants in buildings. Many air pollutants are known to be in higher concentrations indoors than
outdoors. This has a profound effect on health. One of the main reasons to build a green home is
to improve indoor air quality.

13.1 Indoor air pollutants and health: Indoor air quality can have a profound effect on a
person's well being when we spend much time indoors as we do in modern society. The
quality of indoor air is impacted by many sources of air pollutants as well as by building
construction and ventilation. There are many sources of indoor air pollutants. The presence of
indoor air pollutants such as tobacco smoke and radon, or by conditions that promote poor indoor
air quality such as inadequate ventilation or moisture intrusion that can lead to mold growth, are
used as indicators of potential health effects. Levels of fine particles, carbon monoxide, nitrogen
and sulfur oxides, volatile organic compounds (VOCs), radon, and biological contaminants such
as certain molds and dust mites are often higher indoors than outdoors. Some sources of indoor
air pollutants are regulated such as tobacco smoking in public buildings. However, there are no
standards that regulate the levels of most indoor air pollutants allowed in buildings or homes.
Fine particles formed from the combustion of wood and gas impact the lungs and heart. Carbon
monoxide affects the heart and reduces the ability of blood to carry oxygen to body tis-
sues. Nitrogen dioxide is a respiratory irritant and decreases immune and respiratory protective
responses. Sulfur dioxide is an upper airway irritant, but in combination with fine particles irri-
tates the lung as well. Smoking tobacco indoors is a major source of combustion particles and
irritant gases. Gas cook tops and ovens and room-vented gas or kerosene heaters are major
sources of combustion gases, particularly carbon monoxide, nitrogen oxides, and sulfur
oxides.

VOCs (which includes formaldehyde) can irritate eyes and the respiratory tract and can
also impact the nervous system. Sources of VOCs indoors include paint, cleaning and polishing
products, plastics, and composite wood products used in construction. 

The very young and the
old as well as people with existing heart and lung diseases (including asthma) are especially sen-
sitive to indoor air contaminants. A large number of known asthma triggers are found indoors.
Some mold exposures can result in serious infections in immune-compromised
people. 

Conditions that contribute to mold growth in buildings include moisture intrusion and
inadequate ventilation to remove normal indoor moisture. Measures to reduce indoor air pollu-
tants include adequate ventilation, reduction of indoor tobacco smoking, proper venting of com-


                                                14
bustion appliances, use of low VOC emitting cleaners, paints, and building materials, and mois-
ture control in buildings.

13.2 Volatile organic compounds (VOC): Any organic compound which evaporates readily to
the atmosphere. Volatile organic compounds (VOC) are considered a factor in indoor air quality
issues such as sick building syndrome. They are generated by materials as they are used or when
components oxidize. Common artificial sources of VOCs include paint thinners, dry cleaning
solvents, and some constituents of petroleum fuels (eg.gasoline and natural gas. They are often
used in paint, carpet backing, plastics, and cosmetic nail polish.




                                Figure: air flow in green building



 14. MOISTURE CONTROL IN GREEN BUILDING: A green home is:
. Durable
. Sustainable
. Comfortable.
 Water is not only the most important factor affecting a home's durability; it is also the most im-
 portant factor affecting the home's maintenance costs and sustainability.

"Homes last longer in dry areas. Moisture is the enemy. In fact, the biggest enemy your house
has is moisture. If a builder has a problem with the house, 99% of the time it is going to be wa-

                                                 15
ter or water vapor related. If a builder needs to be an expert on anything, it is water control."

Homes get wet during construction, during renovation or with age. The problem, though, is not
that homes get wet but the solutions for moisture control. Homes need a good drying system in
place and it is important that they are dried as quickly as possible.



The concept of drying and the design of homes to dry is part of moisture control. Moisture and
its movement must be controlled from the beginning of the build job to the end of the home's
life. There are several sources of moisture in the home. The most important to control are be-
low.

. Rain.
. Plumbing.
. Ground water.
. "Controlling rain is the single most important factor in the design and construction of dura-
         ble buildings and in the control of mold."
  "Homes must be designed with rain control for the location's climate in mind. For example, we
 get an average of 39 inches of rain a year in the Dallas-Fort Worth area. However, it does not
 come one inch here and one inch there. We get most of the rain in short periods of time in the
 spring and the fall. Homes should be designed like we get 120 inches of rain a year instead of
 39 inches."Other sources of water that need to be kept under control are:

        Moisture from human & animal bodies.
        Moisture from human activities such as cooking, bathing, or washing dishes
        and clothes.
        Exterior moisture and water vapor
        Construction moisture--from building materials.
        Surface water
        Snow and ice damming (not a DFW problem).
These sources might have different significance in different climates (such as snow in Dallas or
snow in Minneapolis). The moisture sources and their climate significance must be considered
when choosing materials for the construction of a home. Moisture moves by a number of
means: capillary flow, vapor flow, air convection, and gravity flow. Each of these mechanisms
is driven by different forces and moves at vastly different rates through different materials. This
also determines the choice of building materials for home construction.



Often walls get wet during the home's construction from rain or other precipitation. Even if
they don't get wet then, they will get wet later from other means--often from both the outside
and the inside of the wall. Consequently both sides but definitely from at least one side. Deal-
ing with moisture is a very complicated subject for a builder to understand, much less for the
general public to understand. And it is often even more complicated in a renovation of an older

                                                 16
home. Choosing a builder who understands water and pays attention to water details is as im-
portant as choosing a builder who understands energy-efficiency. There are two other aspects of
water that must be considered in a green home.
        Water conservation
        Conservation of energy when heating of water

15. PASSIVE SOLAR DESIGN IN GREEN BUILDING:

Passive design is more concerned with cooling the home than heating the home, although there
are a few months of the year where passive design is used for heating. Thermal mass, thermal
chimneys, wing walls, and operable windows are common elements found in good passive de-
sign that are used in the DFW and surrounding area. Thermal mass refers to materials such as
masonry and water used to store heat energy for extended times and function to prevent rapid
temperature fluctuations.
Thermal chimneys create or reinforce the effect of hot air rising and use air movement for cool-
ing purposes. 

Wing walls are vertical exterior partitions placed perpendicular to adjoining
windows to enhance ventilation through windows. A casement window with a vertical
pane opening out creates a mini-wing wall. Operable windows are windows that open.




                                    Figure: passive solar




                                               17
1 6. NOISE ONTROL IN GREEN BUILDING: In green building, the interaction of building
shapes, materials, and openings, as well as the people and other animals occupying the homes,
makes noise control more complex. In addition, the location of the home, say along a busy
street or adjacent to a park, determines what outside noises exist. There are two principal types
of transmission generated inside the building.

1. Airborne sounds travel through walls or floor/ceiling assemblies and can emanate from either
human activities in adjacent living spaces or from mechanical noise within the building sys-
tems.

2. Transmission of sound through the building itself. The most common example of this type of
noise is the footsteps of occupants in living spaces above. This type of noise is more difficult to
control in green building.

16.1 Important Noise Control in Green Building

In central air systems, it is important to baffle any ducts that transmit sound between different
building areas. Shock mounting of systems to control vibration might also be necessary. There
are specific protocols developed for plumbing systems, especially for water supply lines, to
create isolation clamping of pipes within building walls. 

In some green building situations, it
is only a matter of utilizing the best quieting technologies available. Regardless, the green
builder seeks the most cost effective building methods to create a quiet interior (normally 45
dBA).
The best ways to control noise use a combination of these four techniques:
   Absorb it.
   Block it.
   Break up its path.
   Isolate it.
Noise can affect more than comfort, though, as it can become hazardous, especially at high de-
cibels over extended periods of time.

17. EXTERIOR WATER CONSERVATION IN GREEN BUILDING:

17.1 Landscaping a green building: Even when you are harvesting rainwater, you need
drought-resistant landscaping natural to your area. Why?
When your rain-harvesting cisterns are empty from lack of rain, it is likely your area will be in
drought conditions and lawn watering might be restricted. Rain water catchment in green build-
ing: Man has always harvested rainwater, although public water systems have caused us to lose
most of the skills necessary to do this. There is a growing interest in rainwater catchment, how-

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ever, because:

       The escalating environmental and economic costs of providing water by drilling or cen-
       tralized water systems
       Health concerns regarding the source and treatment of polluted waters
       The perception that there are cost efficiencies associated with rainwater harvesting.
       The fact that rainwater harvesting or catchment systems provide a source of soft, high
       quality water
       Systems are usually cost-effective.
17.2 Permeable or pervious paving in green building( Use of porous pavement in green
building):

Permeable paving, pervious paving, and porous paving are terms used to describe paving me-
thods for roads, alleys, driveways, and sidewalks or other walkways that allow the movement
of water and air through the paving material. They have more pervious area than traditional as-
phalt and poured concrete pavement. They are a definite component of green building.


This pervious area allows rainwater to (locally) permeate the soil which:
        Decreases the amount of runoff by up to 90%.
        Facilitates ground water recharge.
        Helps control yard erosion on hilly lots.
        Helps control creek bank erosion on creek lots.
        Helps create a beautifully landscaped yard and neighborhood.
In green new homes and suburbs, porous pavements protect natural watersheds from destruc-
tion. In green remodeling of older homes and built-out areas, replacing impervious paving with
porous solutions rehabilitates the home and neighborhood and area environments.

18. INTERIOR WATER CONSERVATION IN GREEN BUILDING:

18.1. Saving water in a green home: Conservation is the use of water-saving methods to re-
duce the amount of water needed for homes, lawns, and other human uses which ultimately in-
creases water supplies for optimum long-term economic and social benefits.
A green home, wherever it is built, always conserves water. How?

  Low water capacity toilets.
  Flow-restricted shower heads.
  Faucet aerators.
  Hot water circulation system.
  Diverting gray water from bathing, clothes washing, and bathroom lavatories for other suita-
ble purposes.
  Composting toilets.

18.2. Hot water in green building(heating water in green homes):

18.2.1 Solar Hot Water

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A solar hot water system, installed on a south-facing roof, can be integrated with both domestic
water and space heating by way of a highly-insulated, large-capacity hot water storage tank
with heat exchanger coils specifically designed for this integration. A solar hot water system
has a short pay-back time period.
18.2.2. Recirculating Cold Water
In almost every American home there is a waiting period for hot water while the cold water in
the pipes runs down the drain. To engineer an energy-efficient hot-water system:
        Optimize the shortest route for hot water to travel.
        Select the right type of pipe.
        Choose the right size of pipe.
        Install a recirculation loop run by an efficient pump which recalculates cooled water in
        the hot water pipes back to the water heater.
This also adds the convenience of "instant" hot water.

18.1.3 On the Way to the Shower
One builder ran solar-heated hot water through a towel warming tube on the water's path to the
shower. A "warm" touch!

19. INSULATION:

       Continuous layer of insulation is recommended by FEMA (rigid blue board or polyiso-
       cyanurate)

       Increase R value of insulation within cavity provided.

       Install batts correctly ––no bunching, squishing, gaps, holes or mashed down pieces.

       Or use blown cellulose or expanding foam instead.
       Provide a deeper cavity (6 inch rather than typical 4 inch) for more insulation



20. MATERIALS:

Building materials typically considered to be 'green' include rapidly renewable plant materials
like bamboo (because bamboo grows quickly) and straw, lumber from forests certified to be
sustainably managed, ecology blocks, dimension stone, recycled stone, recycled metal, and oth-
er products that are non-toxic, reusable, renewable, and/or recyclable (e.g. Trass, Linoleum,
sheep wool, panels made from paper flakes, compressed earth block, adobe, baked earth,
rammed earth, clay, vermiculite, flax linen, sisal, sea grass, cork, expanded clay grains, coco-
nut, wood fiber plates, calcium sand stone, concrete (high and ultra high performance, roman
self-healing concrete) , etc.) The EPA (Environmental Protection Agency) also suggests using
recycled industrial goods, such as coal combustion products, foundry sand, and demolition de-
bris in construction projects. Polyurethane heavily reduces carbon emissions as well. Polyure-
thane blocks are being used instead of CMTs by companies like American Insuloc. Polyure-
thane blocks provide more speed, less cost, and they are environmentally friendly. Building

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materials should be extracted and manufactured locally to the building site to minimize the
energy embedded in their transportation.




21. CONCLUSION: Building construction and operation have extensive direct and indirect
impacts on the environment. Buildings use resources such as energy, water and raw materials,
generate waste (occupant, construction and demolition) and emit potentially harmful atmos-
pheric emissions. Building owners, designers and builders face a unique challenge to meet de-
mands for new and renovated facilities that are accessible, secure, healthy, and productive
while minimizing their impact on the environment.

             Buildings are the world’s major consumers of energy, and green buildings, which
can reduce energy consumption by 30 to 70%, will enjoy a competitive advantage. This applies
to other resources as well, such as water, waste disposal; etc.But green buildings also create
healthier environments, due to increased fresh air, natural daylight, and the avoidance of toxic
materials.

            The green buildings are better equipped to deal with the emerging set of global
conditions. ―Non-green buildings will become more expensive to run, will find it harder to se-
cure tenants, and will reduce in value. Unless they undergo expensive refitting they will ulti-
mately become obsolete.


“Green buildings are the way of the future, and buildings that are not green will ultimate-
ly become obsolete”.




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Indoor Air Quality




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