environmental science in building 2

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Environmental Science in Building

Chapter 1

The EnvironmentA. Basic Term

1. Natural environment is the entire environment without human presence or

interfaces, including climate, mountain, hills, rivers and lakes, rock and soil, trees

and plants.

2. Built environment is formed by the buildings and other structure that human

construct in the natural environment including water and drainage system,

transportation system, power system, communication system and etc.3. Sustainability is the general idea of meeting the needs of the present without

compromising the need of the future.

. Green or sustainable building is deliberately designed to minimi!e the impact on

the environment and to ma"imi!e efficiency in the use of resources such as

materials, water, and energy over the lifecycle of the building.

B. Connection between Environments

The built environment responds to the local natural environment. Climate is major

factor determining the features of the building , together with the availability of building

materials and skills. #n addition, local traditional and international architecture styles

are also influences the types of building found across the world.

$igure 1. %arts of the environment

The interaction between natural and built environment have effect that cause concern

about&

• Consumption of non'replenish able resource such as fossil fuel

• Consumption of resources without replenishment such as hardwood forests

• (armful changes in local habitat such as deforestation

• (arm full changes in global habitat such as climate change.

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Building Design Building Performance over lifetimeBuilding Construction Building recycling and disposal

Table 1.1 E"ample of environment connection

Natural environmentfeatures

Built environment features

Hot and dry climates )ight colored surface

*oof overhands to provide shade

+pening for bree!es

Courtyard to trap the cooler air

Warm !umid

climate

)ightweight materials

uildings on stilts for ventilation

Cold climate -aturally sheltered sites

(igh insulation

Tightly sealed construction

Snowfalls trong roof for loadloping roofs for discharging snow

Hig! Winds -aturally sheltered sites

)ow sunken buildings

"orest Timbers as construction materials

#oose stone or

$uarries

tone as construction material

Clay soil /ud brick or adobe construction

$ired brick as construction material

Eart!$ua%e &ones )ow rise fle"ible construction

*einforced concrete structures

0voidance of unsecured masonry

C. B'(#T EN)(*+N,ENT

uilding types are varied and include houses, schools, shops, etc. and they are designed

to people living or working inside. The book is focusing on factors or features of

buildings that affect human comfort.

0 building has four maor stages&

1. esign

pecify what we want and how best to do it

2. Construction

uring the stage the building is made, reuiring resource of land, material, energy and

having an impact on the natural environment

3. %erformance

The stage when the building provides the benefit to the occupants but reuired

arrangement for energy supplies, water supplies and also water disposal.

. isposal

This stage is when the building is disassembled and its material and fittings are recycle

or disposal with minimum impact on the environment.



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$igure 1.2 /aor tages in the life of a building

-. C#(,ATE

• Climate is weather variation in a one specific place over a period of time.

• irectly or indirectly, climate has an influence on all human activity, traditional

social characteristic 4such as type of food grown, clothes worn, leisure activities

and the building design5

• The climate in a specific place will also varied by the graphical latitude, season of

the year, altitude and topography, effect of water and atmospheric circulation

Latitude

The geographical latitude of a place on the earth is a measure of its position above or

below the euator and is usually measured by angles in degree. $or note, the intensity of

solar radiation decreases as latitude increase.

The solar radiation and heating effect received from the sun is strongest when it strikes

the Earth surface straight on, at an angle of 67o to the surface.

Season of the Year

The intensity of solar radiation is varies with the season of the year. The orbit of the

earth around the sun is slightly elliptical and the a"is of the Earth is tilt by 23.8 with

respect to the plane that passes through the sun and the euator. The tilt will cause

changes in radiation, length of the day and climate between summer and winter.

$igure 1.3 /otion of Earth around the sun

Altitude and Topography

The height of a place above the sea level affect its climate because the temperature of

the air decrease with the altitude. The air temperature drops by 9.8 oC for each 1777m

increase in altitude



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The surface feature of the Earth or topography also influence the local climate by

affecting the formation of wind, cloud and rain. $or e"ample as humid air from an

ocean sweeps up the slope of a mountain range the air cools, forms cloud and causing

rain or snow to fall. 0s the wind blows down the leeward slopes on the other side of themountain the air usually warms and clouds tend to disappear.

Effect of ater

+cean and large lakes affect climates by reducing the e"treme of air temperature at

place nearby and downwind of them, because the mass of water absorb heat. The air

temperature over the ocean and in place near ocean have smaller variation in air

temperature than at place at the same altitude but well inland.

Atmospheric circulation

0tmospheric circulation means large scale movement of the air. The movement of the

large mases of air in the atmosphere influence climate by producing wind that distribute

heat and moisture. :lobal belts of wind such as trade wind circle the earth and shift

north and south as the season of the year changes. #n the spring they move towards the

poles and in the autumns they shift toward the euator.

$igure 1. Trade ;ind

E.C#(,ATE T/E

$or the purpose of studying the effect of the climate upon building and human comfort,

the four general climate types describe in Table 1.2



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Table 1.2 Climate types

". EN)(*+N,ENT A*+'N- B'(#-(NG

The following general features of local natural environment are important to our choicesof site for building and towns&

a. Availability of drinking ater

b. !rainage of ground

c. Safety from flooding

d. Shelter from prevailing eather

e. "rientation of the sun as appropriate

G. C#(,ATE CHANGE

:lobal warming is an increase in the earth


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#reenhouses #ases

:reenhouse gases are those that have a large influence on the greenhouses effect. ome

significant greenhouse gases&a. ;ater vapor (2+& occurs naturally from the water of the world, not including

cloud and accounts for most of the greenhouse effect of the earth

b. Carbon io"ide C+2= produce by burning of fossil fuel and forest and by all

organic decay. Chimney, motor vehicles e"haust and forest fires are maor

sources

c. /ethane C(= the main component of natural gas supplies, produce by decay of

organic matter and also by the digestion of sheep and cattle

d. -itrogen +"ide -+". The variation o"ide of nitrogen, which are mainly produce

by motor vehicle emission.

e. Chlorofluorocarbons C$Cs= $amilies of chemical compound manufactured for

use in refrigerator and spray cans and for insulation.

#reenhouse gas emission agreement

>yoto protocol is an agreement made between countries to reduce their emission of

carbon dio"ide and five others greenhouse gases.

Environmental comfort

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The physical comfort of the humans greatly depends upon the following physical

factors= temperature, uality of air, lighting environment and acoustic environment.

# | P a g eChapter 1 The Environment

environmental science in building 2

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