WARM AND HUMID CLIMATE

PRESENTED BY-AR.ROOPA CHIKKALGI. BGS SAP

WARM AND HUMID CLIMATE

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▪Costal areas in south India and hilly areas in north eastcomes under this region.

▪Major cities having this climate are Goa, Mumbai,Visakhapatnam, Kolkata, Chennai etc.

▪High humidity, strong sun, glare from the skycharacterize this climate.

▪There are long monsoon periods with heavy rain. But thebreezes, especially in coastal areas, can increasediscomfort considerably.

CHARACTERISTICS OF WARM AND HUMID CLIMATE

➢TEMPERATURE

• IN SUMMER, 30-35ºC DURING DAY & 25-30ºC AT NIGHT.

• IN WINTER, 25-30ºC DURING DAY & 20-25ºC AT NIGHT.

➢HUMIDITY

• HUMIDITY IS VERY HIGH RANGING FROM 70-90%

➢PRECIPITATION

• PRECIPITATION IS VERY HIGH ABOUT 1200 MM/YR.

➢SKY CONDITIONS

• SKY IS FAIRLY CLOUDY.

• CLOUD COVER 60-90%.

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CHARACTERISTICS OF WARM AND HUMID CLIMATE

➢SOLAR RADIATION

• THE INTENSITY OF SOLAR RADIATION IS HIGH DURNING SUMMERS AND MODERATE DURNING WINTERS.

➢WIND

• WIND VELOCITY IS LOW, CALM AND PERIODIC. BUT MAY BE STRONG DURNING RAIN SQUALLS.

➢VEGETATION

• GROWS QUICKLY DUE TO FREQUENT RAINS.

• DIFFICULT TO CONTROL.

• HIGH HUMIDITY ACCELARATES MOULD AND ALGAE GROWTH, RUSTING AND ROTTING.

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• Resisting heat gain:

Measures that are convenient to avoid heat gain are:

(a)Decreasing surface area of the building exposed to the outside.

(b)Using materials that take a longer time to heat.

(c)Providing buffer spaces between the outside and the inside.

(d)Increase the shade of the building in general.

(e)Using materials that reflect heat.

• Promoting heat loss:

To promote heat lost it is essential to ensure:

(a) Building is well ventilated.

(b) Proper ventilation occurs throughout the day.

(c) Humidity levels are reduced as much as possible.

▪Most of the buildings in warm humid climate have sloping roofs to protect from rain

BUILDINGS –WARM HUMID CLIMATE

WARM AND HUMID CLIMATEBUILDING CHARACTERISTICS

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1. BUILDINGS SHOULD BE SPREAD OUT WITH LARGE OPEN SPACES IN BETWEEN FOR UNRESTRICTED AIR MOVEMENT.

2. CROSS VENTILATION IS VERY IMPORTANT. LARGE OPENINGS TO UNOBSTRUCT AIR PATH AND TO ENSURE PROPER VENTILATION.

3. THE OPENINGS SHOULD BE SHADED BY EXTERNAL OVERHANGS.

4 .OUTLETS AT HIGHER LEVELS TO VENT HOT AIR.

5.PROPER WATER PROOFING AND QUICK DRAINAGE OF WATER IS ESSENTIAL DUE TO HEAVY RAINFALL.

WARM AND HUMID CLIMATEBUILDING CHARACTERISTICS

General recommendations for building design inwarm and humid climate

➢ Site:

(a)Landform:

• For flat sites, design consideration for the landform is immaterial.

• In case of slopes and depressions, the building should be located on the wind ward side or crests to take advantage of cool breezes.

(b) Waterbodies:

• Waterbodies are not essential as they would tend to further increase the humidity.

(c) 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 mornings and early afternoon is avoided during the summers.

(C) 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.

BUILDING SPACING SUCH THAT AIR FLOW IS PROMOTED

(2) Orientation and planform:

• As the temperatures are very high, free plans and 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.

ELONGATED PLANS FOR MAXIMUM CROSS VENTILATION

Heat and moisture producing areas like toilets and kitchens must be ventilatedand separated from the rest of the structure.

VENTILATE KITCHENS AND BATHS TO EXHAUST HOT AIR

• Semi open spaces such as balconies, verandahs and porches can beused advantageously for day time activities as well as give protectionfrom rainfall.

• In buildings a central courtyard can be provided with vents at higherlevels to draw away the rising hot air.

WINDOWS AT HIGH LEVEL TO VENT HOT AIR

HIGH PITCHED ROOFS WITH LOUVERS FOR VENTILATION

(3) Building envelope:

(a)Roof:

In addition to providing shelter from rain and heat, the form of the roof should be planned to promote airflow. Vents at the rooftop effectively induce ventilation and draw hot air out.

The openings should be shaded by external overhangs. Outlets at higher levels serve to vent hot air.

OUTLET LARGER THAN INLET

INLET AT LOWER LEVEL AND OUTLET AT HIGHER LEVEL

Examples illustrating how the air movement within a room can be better distributed.

DISTRIBUTE AIR THROUGHOUT THE ROOM

(d) Colour and Texture:

• The walls should be pasted with light pastel shades or white washed 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 finished should be protected from/resistant to the effects of moisture.

▪ REQUIREMENTS IN A HOT AND HUMID CLIMATE:

WARM AND HUMID CLIMATE

▪Minimization of high day temperature.▪Avoiding direct exposure of building surfaces to sun.▪Humidity control.▪Continuous air circulation to reduce heat.▪To create a temperature difference between indoor and outdoor

HOT AND HUMID▪ Orientation and ventilation:▪Semi – open spaces for light and air movement .▪Buildings should be spread out with large open spaces in between for uninterrupted air movement.▪Cross ventilation is very important. large openings to unobstructed air path and to

ensure proper ventilation.

▪The openings should be shaded by external overhangs. Outlets at higher levels to

vent hot air.

▪Proper water proofing and quick drainage of water is essential due to heavy

Rainfall.

WARM AND HUMID▪ Shading:

▪Keep sunlight off of building walls: After aiming the building to catch the breeze, try to face the long sides (with most of the windows) towards the south and north so the roof overhang shades walls and windows in the middle of the day.

▪Shade in the afternoon: Keep west and east sides short to let less of the hot, low angle morning and afternoon sun heat up walls, especially during the hottest season. Be sure you are considering whether the sun is in the northern or southern sky at this time of year.

▪Cover openings on west and east ends. Use few windows and doors. For openings use vertical sunscreens, climbing vines,or shrubs to reduce heat gain on western walls.

HOT AND HUMID▪ Building materials:

The locally available materials which dominate building construction in these climatic zones are;

▪ Timber

▪ Sun dried and kiln burn brick

▪ Thatch and Bamboo

▪ Clay tiles for roofing

Cavity wall detail

Above: typical thatch roof.

Left: half round country clay tiles.

HOT AND HUMID▪ Extensive use of bamboo in building construction.

▪Timber used as vertical and horizontal support.

DESIGN / PLANNING CONCEPTS

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ORIENTATIONOrientation to minimize sun

radiation impact.

STONE PILLARS

CENTRAL

COURTYARDS

• The advantage of courtyard and veranda is proper ventilation and controlled humidity.

• Cross ventilation is done properly.

• Movement of air is perfect in the building by central courtyard.

USE OF STONE