CLIMATOLOGY

ARCHITECTURE FOR
• HOT AND HUMID CLIMATE
• COLD AND DRY CLIMATE
• HOT AND ARID CLIMATE

SUBMITTED BY :-
ANKIT SHARMA, ANKIT GOYAL ,
SHANTANU RISHI , VIPUL JAIN ,
ISHAN RAUTELA , NAITIK SHARMA
HOT & HUMID CLIMATE

In hot and humid climatic regions, high temperatures are accompanied

by very high humidity levels leading to immense discomfort. Cross
ventilation is hence very essential here. Adequate shading measures
are also necessary to protect the building from direct solar radiation.
 WHY THE CLIMATE OF COASTAL AREA
IS HOT AND HUMID?
Places that are close to sea or oceans
have a humid climate as there is large
amount of water vapour in the air.
Actually what happens, land and water
don't get heated at the same rate . Land
gets heated faster so it radiates the
energy , that heats the air above the land,
as a result of which air above the land
gets heated faster than air above the
water bodies. Now hot air is lighter so it
moves up and the surrounding air above
the seas rushes to take its place which
has lots of water vapour in it. This is the
reason for humidity .
• Example , as in India Mumbai
is near the Equator, where
the light from the sun hit's
most directly . The Earth is
tilted, so hence the Equator is
right in front of the sun, &
hence the heat from the sun
is best received there .
General
• WE ALL KNOW THAT OUR HABITAT/ BUILDINGS ETC ARE GREATELY
INFLUENCED BY MANY FACTORS AND THE SINGLE MOST IMPORTANT
FACTOR AMONGST THEM IS CLIMATE OF THAT PARTICULAR REGION/ AREA.

• SO IT IS VERY IMPORTANT
FOR AN ARCHITECT TO
KNOW ABOUT DIFFERENT
REGIONS AND THEIR
CLIMATIC CHARACTERISTICS
SO THAT HE OR SHE CAN
PLAN ACCORDINGLY AND
EFFECTIVELY.
The main design objectives should be:
1. Resisting heat gain
Measures that are convenient to resist unwanted heat gain are:
• Decreasing surface area of the building exposed to the outside.
• Using materials that take a longer time to heat up.
• Providing buffer spaces between the outside and the inside.
• Increasing shading of the building in general.
• Using materials that reflect heat.
 2. Promoting heat loss
To promote heat lost it is essential to ensure :
• Appliances used are well ventilated.
• Proper ventilation occurs throughout the day.
• Humidity levels are reduced as much as possible.
General recommendations for building design in warm and
humid climate are :
 Site

o Landform
• For flat sites, design considerations for the landform is immaterial.

• In case of slopes and depressions, the building should be located on the windward
side or crest to take advantage of cool breezes.
o Waterbodies
• Water bodies are not essential as they would tend to further increase the humidity.
o Open spaces and built form
• Buildings should be spread out with
large open spaces in between for
unrestricted air movement.
• In cities, buildings on stilts can
promote ventilation and cause cooling
at the ground level .
 o Street width and orientation
• Major streets should be oriented parallel to or within 30 of the
prevailing wind direction during summer months to encourage
ventilation in warm and humid regions. A north-south
direction is ideal from the point of view of blocking solar
radiation. The width of the streets should be such that the
intense solar radiation during late morning and early afternoon
is avoided during the summers .
 Orientation and Planform
As temperatures are not very high, free plans can be evolved as long as the house is under
protective shade. An unobstructed air path through the interiors is important to ensure
proper ventilation. The buildings could be long and narrow to allow cross-ventilation. For
example, a singly loaded corridor plan (i.e. one with rooms on one side only) is
preferable over a doubly loaded one.
Heat and moisture producing areas like toilets and kitchens must be ventilated and
separated from the rest of the structure.
Semi-open spaces such as balconies, verandahs and porches can be used advantageously for
daytime activities as well as give protection from rainfall. In multi-storeyed buildings a
central courtyard can be provided with vents at higher levels to draw away the rising hot air.
 Building Envelope
o Roof
In addition to providing shelter from rain and heat, the form of the roof should be
planned to promote air flow . Vents at the rooftop effectively induce ventilation and
draw hot air out .
• Insulation does not provide any additional benefit for a normal RCC roof in a
non-conditioned building . However, very thin roofs having low thermal mass,
such as AC sheet roofing, require insulation as they tend to rapidly radiate heat
into the interiors during daytime . A double roof with a ventilated space in
between can also be used to promote air flow . The space in between can also
act as a heat buffer.
o Wall
• The walls must also be designed to
promote air flow so as to counter the
prevalent humidity. Baffle walls, both
inside and outside the building can help to
divert the flow of wind inside.
• They should be protected from the heavy rainfall prevalent in such areas . If
adequately sheltered, exposed brick walls and mud plastered walls work very well
by absorbing the humidity and helping the building to breathe .
 o Fenestration
• Cross-ventilation is of utmost importance in warm and humid climatic regions. All
doors and windows should preferably be kept open for maximum ventilation for
most of the year. These must be provided with venetian blinds or louvers to shelter
the rooms from the sun and rain, as well as for the control of air movement.
Openings of a comparatively smaller size can be placed on the windward side, while
the corresponding openings on the leeward side should be bigger for facilitating
natural ventilation.

• The openings should be shaded by external overhangs. Outlets at higher levels serve
to vent hot air.
o Colour and texture
• The walls should be painted with light pastel shades or whitewashed, while the
surface of the roof can be of broken glazed tile(china mosaic flooring) to reflect the
sunlight back to the environment, and hence reduce heat gain of the building . The
use of appropriate colours and surface finishes is a cheap and very effective technique
to lower indoor temperatures . The surface finish should be protected from/ resistant
to the effects of moisture.
Remarks
• Ceiling fans are effective in reducing the level of discomfort in this type of climate .
Desiccant cooling techniques can also be employed as they reduce the humidity level .
Careful water proofing and drainage of water are essential considerations of building
design due to heavy rainfall . In case of air conditioned buildings, dehumidification
plays a significant role in the design of the plant.
COLD & DRY CLIMATE
COLD and SUNNY type of climate is experienced here
Mountainous region Little vegetation Considered to be a ‘Cold Desert’.
• TEMPERATURE VARIATIONS
Summer during day : 17 - 24°C
during night : 4 - 11°C
• Winter during day : 7 - 9°C
during night : -14 – 0 °C
• Relative humidity – consistently low : 10-50%
• Winds – occasionally intense
• Sky is fairly clear throughout the year Cloud cover is less than 50%
DESIGN CRITERIA AND FEATURES
 Resist heat loss
1. Decrease exposed surface area
2. Increase thermal resistance
3. Increase thermal capacity (Time lag)
4. Increase buffer spaces
5. Decrease air exchange rate
6. Increase surface absorptivity
 Promote heat gain

1. Reduce shading
2. Utilize heat from appliances
3. Trapping heat
PHYSICAL MANIFESTATION
1. Orientation and shape of building. Use of trees as wind barriers
2. Roof insulation, wall insulation and double glazing
3. Thicker walls
4. Air locks/ Lobbies
5. Weather stripping
6. Darker colors
7. Walls and glass surfaces
8. Sun spaces/ green houses/ Trombe walls etc
• TREES
wind barrier Roof & wall insulation Thick walls Heavy walls (mud) and a well
insulated roof (timber & mud) dampen the variations of indoor temperatures.

• Use of glass and trombe wall

heat is stored in the building mass during the day and warm during the night
LEH, LADAKH
City of some 25,000 inhabitants Population triples in size during summer tourist season
OLD LEH
• 200 stone, mud and timber houses sandwiched between thick rammed earth walls
• Most well-preserved traditional Tibetan city in the world
• Most significant ensemble of historic Tibetan architecture
• One makes the walls for the first floor, piling up stone and sun-dried brick,
• and then places wooden beams and floor joists across the walls to support the second
floor walls above them,
• and repeatedly adds more wooden beams across them.
• Floors and roofs are made of mud treaded on wooden boards.
• Roofs are basically flat, being unnecessary to waterproof, since it scarcely ever rains.
• Columns are needed midway across larger spans

• First floor - used for stables

• Second floor – for family rooms, such as a sitting room, a kitchen, bedrooms, and a
Buddhist altar room
• A larger house often consists of three floors.
 ARCHITECTURE OF HOT AND ARID CLIMATE
• THIS TYPE OF CLIMATE PREVAILS AROUND 15 DEGREE FROM EQUATOR IN
THE NORTHERN HEMISPHERE AND 30 DEGREES FROM EQUATOR IN
SOUTHERN HEMISPHERE.
• IN INDIA THIS TYPE OF CLIMATE CAN BE EXPERIANCED IN RAJASTHAN,
GUJRAT , MAHARASHTRA AND SOME PARTS OF MADHYA PRADESH AND
KARNATKA ALSO .
CHARACTERISTICS OF HOT AND ARID CLIMATE
 TEMPERATURE
• IN THIS TYPE OF CLIMATE TEMPERATURE IS
USUALLY VERY HOT.
• IT CAN VERY EASILY GO UPTO 50* AND EVEN
MORE IN SUMMERS.
• THE DIFFRENCE BETWEEN DAY AND NIGHT
TEMPERATURE IS VERY HIGH (15 TO 20
DEGREE CELSIES)

 SOLAR RADIATIONS
• SOLAR RADIATIONS ARE DIRECT AND STRONG DURING DAY TIMES. AND
THESE OFTEN ESCAPES INTO OPEN CLEAR SKIES DURING NIGHTS.
 PRECIPITATION
• AS THE AIR IS TOTALLY HOT & DRY IN THIS TYPE OF CLIMATE .
PRECIPITATION IS VERY LOW . IT MAY VARY BETWEEN 50 TO 150 mm PER
YEAR.

 SKY CONDITIONS
• SKY IS NORMALLY CLEAR AND BLUE IN THIS TYPE OF CLIMATE . SOME TIMES
DUST STORMS FILL COMPLETE SKY . AND THESE DUSTY SKIES CREATE
UNBERABLE GLARE.
 WIND
HIGH SPEED DUSTY WINDS ARE VERY COMMON FOR THIS TYPE OF
CLIMATE .WIND SPEED MAY VARY BETWEEN 20 TO 30 KILOMETER PER
HAUR .WIND OFTEN CHANGE DIRECTIONS LOCALLY.

 SOIL AND VEGITATION

SOIL IS VERY LOOSE AND SANDY LOW HUMIDITY AND LESS RAIN FALL RESULTS
IN POOR VEGETATION . ONLY THICK LEAVES AND THORNY PLANTS CAN EASILY
SURVIVE HERE.
 MAIN AIM / DESIGN THRUST
• ARCHITECTS MAIN AIM IS TO AVOID HOT SUN AS FAR AS POSSIBLE.
• TO CAPTURE AS MUCH COOL AIR AS POSSIBLE.
• TO PROVIDE PROTECTION FROM DUST STORMS.
• RURAL ARCHITECTURE
• EXTERNAL LOOK IS ALMOST DEAD TO AVOID SUN,
• EXTERIOR IS LIGHT IN COLOUR AGAIN TO AVOID ABSORPTION OF HEAT.
• SURFACE AREA EXPOSED TO SUN IS MINIMUM.
• THICKER MUD WALLS ACT AS GOOD INSULATING MATERIALS.
• SMALLER SIZE OF WINDOWS LIMITS GLARE OF SOLAR RADIATIONS.
• STREETS ARE NARROW.
• UNITS ARE VERY CLOSELY PLACED.
DESIGN CRITERIA / PLANNING CONCEPTS
 SITE
A. SITE SHOULD BE NEAR THE SOURCE OF WATER.

B. AND IT IS ALWAYS BETTER TO BUILD TOWARDS LEEWARD

SIDE OF AN IRRIGATED AREA BECAUSE THE MOISTURE OF
IRRIGATED AREA MAY LOWER THE AIR TEMPERATURE.

C. NARROW VALLEYS SHOULD BE AVOIDED BECAUSE THIS

MAY BECOME SOLAR TRAPS WITH THE MOUNTAIN SIDES
HEATING AND RADIATING HEAT BACK AND FORTH.
 ORIENTATION
A. NORTH –SOUTH ORIENTATION BEST SUITS FOR THIS TYPE
OF CLIMATE AS IT PROTECTS FROM MORNING AND
EVENING SOLAR RADIATIONS.

B. APART FROM THIS LOCAL SITE CONDETIONS AND ITS

SURROUNDINGS ALSO PLAYS MAJOR ROLE IN DECIDING
ORIENTATION .

C. BEDROOMS SHOULD BE ORIENTED TO RECEIVE COOL

NIGHT AIR.
 HOUSE PLANS
A. COMPACT PLANS ARE PREFFRED AS THESE WILL EXPOSE
MINIMUM SURFACE TO HARSH SOLAR RADIATIONS.
B. DEEPER ROOMS ARE BETTER AGAINST HOT OUTSIDE
SOLAR RADIATIONS.
C. INWARD LOOKING PLANS BEST SUITS FOR THIS TYPE OF
CLIMATE AS THESE STRAIGHT AWAY PROTECT US FROM
EXTERNAL SOLAR HEAT AND RADIATIONS
D. COURTYARD PLANNING ALONG WITH SOME TREES AND
SMALL WATER BODY CREATES VERY GOOD COOL
MICROCLIMATE AS EVAPORATIVE COOLING EFFECTS
OCCURES IN THIS TYPE OF COURTYARD.
 ROOFS
A. ROOFS SHOULD BE MADE HIGHER SO THAT RADIATIONS FROM
CEILING IS LESS HARSH AND THERE IS ENOUGH SPACE FOR HOT
DICIPATED AIR.

 WALLS
A. THE WALLS OF DAY TIME LIVING AREAS SHOULD BE MADE OF HEAT
STORING MATERIALS SO THAT THESE CAN STORE HEAT IN DAY TIME
AND KEEP THE INSIDE COOL AND RADIATE HOT SOLAR RADIATION
BACK IN TO ATMOSPHERE DURING NIGHT.
B. EASTERN AND WESTERN WALLS SHOULD BE SHADED WITH TREES OR
SOME OTHER SCREENS.
 OPENINGS
A. EXTERNAL OPENINGS SHOULD BE SMALL.
B. EASTERN AND WESTERN SIDE WINDOWS SHOULD BE PROTECTED BY
TREES.
C. LARGE GLASS AREAS SHOULD BE AVOIDED.
D. DEEP SUN SHADES ARE REQUIRED TO SHADE WINDOWS
EFFICTEVELY.
E. 5. IT WOULD BE MORE EFFECTIVE,IF WE SOME HOW ,SEPARATE OUR
SUN SHADES FROM MAIN STRUCTURE .
 INTERIORS

A. LIGHT COOL COLOURS SHOULD BE USED FOR INTERIORS .

B. SURFACES THAT MAY REFLECT RADIATIONS SHOULD BE PAINTED
DARK TO REDUCE GLARING EFFECT.
 SOME CONSTRUCTION TECHNIQUES
• WIND TOWER AT HIGHER LEVEL TO CATCH DUST FREE WIND AND
TRANSFER IT INTO BUILDING.
• CAVITY WALLS ALSO HELP IN LIMITING PENETRATION OF SOLAR HEAT AND
RADIATIONS INSIDE BUILDINGS
• SHOWING DOUBLE GLAZED WINDOWS WHICH LETS THE LIGHT COME IN
AND KEEP THE HEAT OUT.
• HOLLOW BLOCK CONSTRUCTION TECHNIQUE ALSO HELP IN THERMAL
INSULATION OF BUILDINGS.
• DOUBLE ROOF TECHNIQUE PROTECT MAIN STRUCTURE FROM SOLAR HEAT
• HOT SOLAR RADIATIONS CAN BE CONVERTED IN USEFULL ELECTRICITY BY
USING PHOTOVOLTIC CELLS.
• SUN PROTECTION DEVICES(PERGOLAS) ARE USED TO PROTECT FRONT
FACADES OF HOT ARID REGION.
• GLASS FAÇADE OF BUILDING IS PROTECTED BY DEEPER EAVES/ OVERHANG
AT ROOF LEVEL.
• USE OF DEEPER ENTRANCE DOOR AND BROAD EAVES