global warming,sustainable architecture and architect's role

8/13/2019 Global Warming,Sustainable Architecture and Architect's Role

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SUSTAINABLE ARCHITECTURE-SEM IX

SUBMITTED BY:TEJASI GADKARI

30/08

ASSIGNMENT-1


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Global warming refers to the effect on the climate of human activities, in particular theburning of fossil fuels (coal, oil and gas) and large-scale deforestation activities that havegrown enormously since the industrial revolution, and are currently leading to the release ofabout 7 billion tonnes of carbon as carbon dioxide into the atmosphere each year togetherwith substantial quantities of methane, nitrous oxide and chlorouorocarbons (CFCs). Thesegases are known as greenhouse gases.

PRINCIPLE OF GLOBAL WARMING:can be understood by considering the radiationenergy from the sun that warms the Earths surface and the thermal radiation from the Earthand the atmosphere that is radiated out to space.

Many of the likely characteristics of the resulting changes in climate such as :More frequent heat waves,Increases in rainfall,

Increase in frequency andIntensity of many extreme climate events

Q. What do you understand by global warming? Explain various reasons ofglobal warming.

The effect was rst recognized by the French scientist Jean-Baptiste Fourier in 1827.

A British scientist, John Tyndall around 1860 measured the absorption of infrared radiation bycarbon dioxide and water vapour and suggested that a cause of the ice ages might be adecrease in the greenhouse effect of carbon dioxide.

The planet is warming, from North Pole to South Pole. Globally, the mercury is already up morethan 1 degree Fahrenheit (0.8 degree Celsius), and even more in sensitive polar regions. Theheat is not only melting glaciers and sea ice, its also shifting precipitation patterns and settinganimals on the move.


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CAUSES OF GLOBAL WARMING

Natural Man made

Release of methane gas fromarctic tundra and wetlands.

Earths cycle of climate change.This climate change usually lastsabout 40,000 years.

Burning fossil fuels.

Concentration of Green Housegases like CO 2 ,methane,nitrousoxide in the atmosphere.

Deforestation

Population explosion

NATURAL CAUSES:Natural causes are causes created by nature. One natural cause is arelease of methane gas from arctic tundra and wetlands. Methane is a greenhouse gas. A

greenhouse gas is a gas that traps heat in the earth's atmosphere. Another natural cause isthat the earth goes through a cycle of climate change. This climate change usually lastsabout 40,000 years.

MAN-MADE CAUSES: Pollution, burning fossil fuels, Since CO2 contributes to globalwarming, the increase in population makes the problem worse because we breathe outCO2. Also, the trees that convert our CO2 to oxygen are being demolished because we'reusing the land that we cut the trees down from as property for our homes and buildings.


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The main reason behind global warming is the increase in the concentrationof greenhouse gases in the atmosphere due to green house effect. Green house effectleads to increase in the temperature of earth by trapping the sun's heat and light in theearth's atmosphere.

In this phenomenon the heat and light of sun enters the atmosphere but cannot go outas they are trapped in earth's atmosphere by the green house gases and thus resulting intemperature rise. The green house gases like carbon dioxide, methane, and nitrous oxideplays the major role in green house effect and excessive emission of these gases throughvarious means is a major cause of global warming.

Another important reason for global warming islarge amounts of carbon dioxide produced from burning of fossil fuels for the differentpurposes especially for power generation in various power plants.

Due to burning of large amount of coal in power plant excessive amount of carbondioxide is emitted in different forms in the atmosphere. In addition to that, countlessnumber of vehicles running in the road today is one of the major source of emission of alarge amount of carbon dioxide in the atmosphere leading to increase in the temperatureof earth's atmosphere.

Methane is another green house gas that results in global warming to a large extent.Methane can be easily obtained from rice paddies, bovine flatulence, bacteria in bogs andfossil fuel manufacture and hence easily available in abundance.

Moreover, it is 20 times as effective as Carbon dioxide at entrapping heat in theatmosphere and is a leading cause of global warming. Similarly, another green house gascalled nitrous oxide and chlorofluorocarbons or CFCs is also responsible for the globalwarming. Nitrous oxide has 300 times more capacity of trapping heat than carbon dioxidewhile chlorofluorocarbons have heat-trapping potential thousands of times greater thancarbon dioxide.

Another major cause of global warming is continuous cutting of a large number of treesacross the world that is also referred as deforestation . It is projected that, 34 million acresof trees are cut and burned each ear resulting in 25% of all carbon dioxide release enteringthe atmosphere.

Increasing population is another cause of global warming that cannot be neglected. Ashuman being is known to exhale carbon dioxide means more population will lead to moreemission of carbon dioxide in the atmosphere resulting in increase in the level of carbondioxide in the atmosphere and thus resulting in global warming.

MAJOR CAUSES OF GLOBAL WARMING


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Q. What is sustainable architecture and what is the role of an architect.?

Sustainable architecture is a general term that describes environmentally consciousdesign techniques in the field of architecture.

Sustainable architecture is framed by the larger discussion of sustainability and thepressing economic and political issues of our world.

Oxford Dictionary denes sustainability as : able to be maintained at a certain rateor level: sustainable fusion reactions.Ecology (esp. of development, exploitation, or agriculture) conserving an ecologicalbalance by avoiding depletion of natural resources.

Able to be upheld or defended: sustainable denitions of good educational practice

In the broad context, sustainable architecture seeks to minimize the negativeenvironmental impact of buildings by enhancing efficiency and moderation in the useof materials, energy, and development space.

IDEA OF SUSTAINABILITY:To ensure that our actions and decisions today do notinhibit the opportunities of future generations.

The term can be used to describe an energy and ecologically conscious approach tothe design of the built environment.

ATMOSPHERE EQUITY

LONGEVITY

ENERGY

INTERFACE

ASPECTS OF SUSTAINABLE ARCHITECTURE

The key to architectural sustainability is to work with , rather than against Natur e; to besensitive so that we do not damage the natural systems. Architectural sustainability mirrorsthe view that it is necessary to position human activities as a non-damaging part of theongoing ecological landscape, with a belief that nature knows best.


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COMPONENTS OF A SUSTAINABLE ARCHITECTURE

ATMOSPHERE: of a building is the mood and feeling that it engenders.A sustainable buildingwill take into account all of these factors because the health of a buildings users is intrinsicallyintertwined with the use of the building.

LONGEVITY:of a building also plays an important role in its sustainability.

Spaces that remain of use to their occupants for a long duration are more sustainableDesigning buildings that will last and be of use for generations should be a major goal of anyarchitect.

ENERGY: Reducing the energy impact of a built space is one of the most importantconsiderations to be taken when constructing spaces. Building energy use comes intwo forms: embodied energy and operating energy .Embodied energy , the energy required to create, transport and install the materials that makeup a building, surprisingly make up a large portion of a buildings energy costs (less if thebuilding lasts longer).Operating energy is the energy a building uses everyday to heat andcool a space, run appliances and power any electronics within.

INTERFACE:A building that interfaces well with its surroundings is one that is more usefuland likely to be appreciated for longer. Also of importance is how the building affects theimmediate environment, i.e. what plants and animals are being displaced, how much of thelocal topography will be changed, will weather systems be signicantly impacted by the newbuilding (such as from storm water or wind)?

ROLE OF AN ARCHITECT

Any green building architect should identify places with intrinsic suitability for agriculture,forestry, recreation and urbanisation.

Designing with nature at a building level is about recognizing sun paths, breezes, shade treesand rock formations that can be used to create something that people can inhabitcomfortably, while recognizing that natural features such as trees, animal tracks, habitats andnatural drainage systems must be protected.

For example, if one is to choose a device with high shading coefficient in the summer and alow shading coefficient in the winter, a vine may be used in place of a mechanical system .The vine shades the building when it is needed, and the building provides a home for thevine. Thus, both are sustainable.

50 per cent reduction can be made by siting, fenestration, and orientation of buildings workwith the local environment, so that buildings take advantage of passive heating and coolingand natural lighting. Approximately 15 percent of all energy in houses is used for domestichot water. Using solar water heating is not a new technology. The payback on that sort of

system is three to five years.

By adding rainwater collection , reed beds for sewage and perhaps wind or solar power forelectrical energy, the building can be independent of imported service and exported waste,keeping its environmental footprint within the footprint of the site. The final archetypal visualimage is one of an isolated, self-sufficient building dominated by its surrounding landscape.


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STRATEGIES OF SUSTAINAIBILITY1. Conserve Energy1. Cities: Reduce automobile use, Build compact cities, Public transit, pedestrian environment2. Buildings : Insulation, orientation, passive and active solar energy.Day lighting. Shading, Sustainable sources of materials

2. Reduce Heat Island effect

1. Bring landscape into city for shade, air quality and delight. Plant trees forshade, green roofs, green corridors, reduce paving

3. Reduce Pollution1. Recycle. Control sources for pollution, Regulate emissions, findalternatives to polluting substances.

4. Conserve Water1. Return rainwater to ground (permeable paving). Native landscapingrequires less irrigation. Reuse gray water. Treat sewage to high degree.

5. Conserve Wildlife1. Protect wildlife habitat. Habitat corridors through city. Design habitats fornative wildlife (parks for animals and people

Wildlife corridors bring native ecosystem into city. Tukwila, Washington,WildlifeCorridors,University of Washington


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ENERGY-CONSCIOUS SITE PLANNINGSuch planning allows the designer to maximize the use of natural resources on the site. Intemperate climates, open southern exposure will encourage passive solar heating; deciduoustrees provide shade in summer and solar heat gain in winter. Evergreens planted on the north

of a building will protect it from winter winds, improving its energy efficiency. Buildings can belocated relative to water onsite to provide natural cooling in summer.

PASSIVE HEATING AND COOLINGSolar radiation incident on building surfaces is the most significant energy input to buildings.It provides heat, light, and ultraviolet radiation necessary for photosynthesis. Historically,architects have devised building forms that provide shading in summer and retain heat inwinter. This basic requirement is often overlooked in modern building design. Passive solararchitecture offers design schemes to control the flow of solar radiation using buildingstructure, so that it may be utilized at a more desirable time of day.

Shading in summer , by plants or overhangs, prevents summer heat gain and theaccompanying costs of air-conditioning.The wind, or the flow of air, provides two majorbenefits: cooling and hygienic effects. Prevailing winds have long been a major factor in urbandesign. For instance, proposals for Roman city layouts were primarily based on the directionof prevailing winds.


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INSULATIONHigh-performance windows and wall insulation prevent both heat gain and loss. Reducingsuch heat transfer reduces the buildings heating and cooling loads and thus its energyconsumption.

Reduced heating and cooling loads require smaller HVAC equipment, and the initialinvestment need for the equipment will be smaller.

High-performance windows and wall insulation create more comfortable thermalenvironments. Due to the insulating properties of the materials, the surface temperatures ofwindows and walls will be higher in the winter and lower in the summer.

The i nstallation of smaller HVAC equipment reduces mechanical noise and increases sonicquality of the indoor space.

ALTERNATE SOURCES OF ENERGYSolar, wind, water, and geothermal energy systems are all commercially available to reduce oreliminate the need for external energy sources. Electrical and heating requirements can bemet by these systems, or combination of systems, in all climates.

DAYLIGHTINGBuilding and window design that utilizes natural light will lead to conserving electricallighting energy , shaving peak electric loads, and reducing cooling energy consumptions. Atthe same time, day lighting increases the luminous quality of indoor environments, enhancingthe psychological wellbeing and productivity of indoor occupants.

ENERGY-EFFICIENT EQUIPMENT & APPLIANCESAfter construction costs, a buildings greatest expense is the cost of operation . Operationcosts can even exceed construction costs over a buildings lifetime.Careful selection of highefficiency heating, cooling, and ventilation systems becomes critical. The initial price of thisequipment may be higher than that of less efficient equipment, but this will be offset byfuture savings.

Appliances, from refrigerators to computers, not only consume energy, they also give off heatas a result of the inefficient use of electricity . More efficient appliances reduce the costs ofelectricity and air-conditioning.

CHOOSE MATERIALS WITH LOW EMBODIED ENERGYBuilding materials vary with respect to how much energy is needed to produce them. Theembodied energy of a material attempts to measure the energy that goes into the entire lifecycle of building material.

For instance, aluminium has a very high embodied energy because of the large amount ofelectricity that must be used to manufacture it from mined bauxite ore ; recycled aluminumrequires far less energy to refabricate.

By choosing materials with low embodied energy , the overall environmental impact of abuilding is reduced. Using local materials over imported materials of the same type will savetransportation energy.


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WATER CONSERVATIONMethods for water conservation may reduce input, output, or both. This is because,conventionally, the water that is supplied to a building and the water that leaves thebuilding as sewage is all treated by municipal water treatment plants. Therefore , areduction in use also produces a reduction in waste.

REUSE WATER ONSITE

Water consumed in buildings can be classified as two types: graywater and sewage.Graywater is produced by activities such as handwashing. While it is not of drinking-water quality, it does not need to be treated as nearly as intensively as sewage.In fact, it can be recycled within a building, perhaps to irrigate ornamental plants orflush toilets. Well-planned plumbing systems facilitate such reuse .

Rainwater falling on buildings has not been considered a useful resource. Buildings aretypically designed to keep the rain from the occupants, and the idea of utilizing rainwater falling on building surfaces has not been widely explored.

Building envelopes , particularly roofs, can become rainwater collecting devices , incombination with cisterns to hold collected water. This water can be used for irrigationor toilet-flushing.

REDUCE CONSUMPTIONWater supply systems and fixtures can be selected to reduce consumption and waste .Low-flow faucets and small toilet tanks are now required by code in many areas of thecountry. Vacuum-assisted and biocomposting toilets further reducewater consumption.

Biocomposting toilets, available on both residential and commercial scales, treatsewage on site, eliminating the need for energy-intensive municipal treatment.Indigenous landscaping using plants native to the local ecosystem will also reducewater consumption.

These plants will have adapted to the local rainfall levels , eliminating the need foradditional watering. Where watering is needed, the sprinkler heads should be carefullyplaced and adjusted to avoid watering the sidewalk and street.

MATERIAL CONSERVATION

ADAPT EXISTING BUILDINGS TO NEW USESOne of the most straightforward and effective methods for material conservation is tomake use of the resources that already exist in the form of buildings. Most buildingsoutlive the purpose for which they were designed. Many, if not all, of these buildingscan be converted to new uses at a lower cost than brand-new construction.

INCORPORATE RECLAIMED OR RECYCLED MATERIALSBuildings that have to be demolished should become the resources for new buildings.Many building materials, such as wood, steel, and glass, are easily recycled into newmaterials.Some, like brick or windows, can be used whole in the new structure.Furnishing, particularly office partition systems, are also easily moved from one locationto another.


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EXAMPLES OF SUSTAINABLE ARCHITECTURE

VILLAGE HOMES, DAVIS CALIFORNIA Energy conservation Water retention Pedestrian community Narrow Streets Pedestrian paths, Surface swales for water retention, Park corridors Passive solar heating

MULTIPURPOSE STREETuse forpedestrian,bicycles,cars in Copenhagen

Ken Yeang,Menara BousteadMalaysia


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Location of Core, Central vs. Flanking core on

East and West

Shading Screens

on North andSouth

Recessed Balconies

Raised Base Green Walls Wind Scoops Cross ventilation

BUILDING TECHNIQUES

Solar shading Solar collectors Insulation on east andwest humid climates

Mass on east andwest arid climates


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BUILDING TECHNIQUES

Double skin Design

RENZO PIANO DEBIS TOWER, BERLIN,1999

NORMAN FOSTER, REICHSTAG DOME, BERLIN, 1999


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USE MATERIALS THAT CAN BE RECYCLEDDuring the process of designing the building and selecting the building materials , lookfor ways to use materials that can themselves be recycled . This preserves the energyembodied in their manufacture.

SIZE BUILDINGS AND SYSTEMS PROPERLYA building that is oversized for its designed purpose , or has oversized systems, will

excessively consume materials . When a building is too large or small for the numberof people it must contain, its heating, cooling, and ventilation systems,typically sizedby square footage, will be inadequate or inefficient.

REUSE NON-CONVENTIONAL PRODUCTS AS BUILDING MATERIALSBuilding materials from unconventional sources , such as recycled tires, pop bottles,and agricultural waste, are readily available . These products reduce the need for newlandfills and have a lower embodied energy that the conventional materials they aredesigned to replace.

CONSUMER GOODSAll consumer goods eventually lose their original usefulness .The useful life quantifies the time of conversion from theuseful stage to the loss of original usefulness stage. For instance, a daily newspaper isuseful only for one day, a phonebook is useful for one year, and a dictionary might be usefulfor 10 years. The shorter the useful life of consumer goods , the greater the volumeof useless goods will result. Consequently, more architectural considerations will berequired for the recycling of short-life consumer goods.

global warming,sustainable architecture and architect's role

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