climate BOOK MANUAL OF TROPICAL HOUSING AND BUILDING TOPIC 7.1 Shelter for hot-dry climate 7.2 Shelter for warm-humid climates

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1 climate BOOK MANUAL OF TROPICAL HOUSING AND BUILDING TOPIC 7.1 Shelter for hot-dry climate 7.2 Shelter for warm-humid climates

2 Nature of the climate HOT - DRY CLIMATES HOT DRY AND SEMI DESERT CLIMATES VERY HOT DRY AIR AND DRY GROUND DAY TIME AIR TEMPERATURE : 27 TO 49 C ( > THAN SKIN TEMPERATURE 36 TO 37 C) NIGHT TIME AIR TEMPERATURE : 22 C (FALLS) LOW HUMIDITY NO CLOUD COVER ( FROM DIRECT SOLAR RADIATION )

3 Nature of the climate WARM HUMID CLIMATES AIR TEMPERATURE : 21 TO 32 C (LITTLE VARIATION IN DAY AND NIGHT) ( OFTEN EXCEEDS NORMAL SKIN TEM.) HIGH HUMIDITY (ALL SEASONS ) HEAVY CLOUD AND WATER VAPOUR MOSTURE WITH MODRATE HEAT AND HIGH RAIN FALL PLANT COVER WIND

4 Nature of the climate

5 Nature of the climate Warm-humid climate

6 Physiological objectives HOT DRY CLIMATE it is the PHYSICAL HUMAN COMFORT FROM THE ENVIOURMENT. PHYSICAL COMFORT OF HUMAN PER DAY DEPENDS ON THE REDUCTION OF THE INTENCE RADIATION FROM SUN, GROUND AND SURROUNDING BUILDINGS. MAINTAINANCE OF INNER SURFACE TEMP. is LESS THaN THE SKIN TEMP. THE BODY DISSIPATE SOME OF ITS HEAT TO THE SURROUNDING MAKING TEMP. COOL BY CONVECTION. NIGHT AT NIGHT THE AIR TEMP. IS FREQUENTLY LOW PERMITS EFFECTIVE TEMP. ( TEMP. OF COMFORT ). SUCH EFFECTIVE TEMP. AT NIGHT BECOMES BENEFICIAL. DUE TO LOW HUMIDITY EVAPORATION IS HIGHER COMPARED TO OTHER CLIMATE. SPECIAL ARRANGEMENT IS NOT NECESSARY EG. A.C COOLER ETC.

7 Physiological objectives HOT DRY CLIMATE DAY TIME CLIMATE IS TOO HOT DURING DAY, ARRANGEMENTS ARE REQUIRED AS THE AIR IS NOT COOLED AND DUST FILTERED.

8 Physiological objectives WARM-HUMID CLIMATE TEMP. IS NEAR TO SKIN TEMP. HEAT IS TRASMITTED BY CONVECTION AND CONDUCTION, WHICH IS NEGLIGIBLE FOR PHYSICAL COMFORT THERE SHOULD BE HEAT DISSIPATION FROM BODY=TO THE AMOUNT OF METABOLIC HEAT PRODUCTION OF THE BODY. HIGH HUMIDITY - SATURATED AIR ENVELOPE - BLOCKING EVAPORATION CYCLE prevention THE SATURATION CAN BE AVOIDED BY ALLOWING OUTSIDE BREEZE TO PASS THROUGH THE BUILDING AND TO THE OCCUPANTS. AT NIGHT. NO SIGNIFICANT COOLING IS DONE. THE WALL AND ROOF SURFACE TEMP. SETTLE DOWN TO THE SAME LEVEL AS THE AIR TEMP.

9 Physiological objectives WARM-HUMID CLIMATE

10 Form and planning HOT-DRY CLIMATE LESS ACCOMODATION UNDER ONE ROOF - LESS HOT AIR AND THERMAL LOADING FROM THE SUN. LARGER DIMENSIONS OF THE BUILDING SHOULD PREFERABLY FACE NORTH AND SOUTH. WORST ORIENTATION IS WEST. NON - HABITABLE ROOMS CAN BE USED AS THERMAL BARRIERS. SHADING OF ROOFS,WALLS AND OUTDOOR SPACES IS CRITICAL. LOW THERMAL CAPACITY MATERIALS SHOULD BE USED FOR SHADING DEVICES. TO HAVE CLOSE GROUPS OF BUILDINGS,NARROW ROADS AND STREETS, ARCADES, COLLONADES AND SMALL ENCLOSED COURTYARDS GET MAXIMUM AMOUNT OF SHADE AND COOLNESS. DIFFICULT SHADING OF ROOF DOUBLE ROOF IS PREFFERED. NECESSIATE THE USE OF METAL SURFACE.

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12 Form and planning WARM-HUMID CLIMATE AIR MOVEMENT IS THE ONLY AVAILABLE RELIEF FROM CLIMATIC STRESS. ELONGATED PLANS,IN A LINEAR, ACROSS THE PREVAILING WIND DIRECTION,AFFORD LOW RESISTANCE TO AIR MOVEMENT AND IS THEREFORE THE IDEAL SOLUTION.

13 Form and planning Hot dry climate Warm humid climate

14 Form and planning Hot-dry climate

15 Form and planning Hot-dry climate

16 Form and planning Hot-dry climate

17 Form and planning Warm-humid climate

18 Form and planning Warm-humid climate

19 Form and planning Warm-humid climate

20 External space HOT-DRY CLIMATE EXTERNAL SPACES ARE NECESSARY TO TREAT AS IMPORTANTLY AS THE BUILDING. ADJACENT BUILDINGS, PAVEMENTS (FOOTPATH KIND OF) HEAT UP QUICKLY DRY GROUND NIGHT RERADIATE THE HEAT STORED DURING THE DAY. DAY PAINFUL GLARE RELECT HEAT RADIATION TOWARDS THE BUILDING DURING THE DAY. TREES, PLANTS, WATER body WILL COOL THE AIR BY EVAPORATION. thermal regulators :- 1. courtyard 2. water body WATER BODY COOL AIR at night IS RETAINED, AS cool AIR IS HEAVIER THAN THE SURROUNDING WARM AIR.

21 External space WARM-HUMID CLIMATE EXTERNAL SPACES SHADING FREE PASSAGE [IMPORTANT FOR AIR MOVEMENT IN EXTERNAL SPACES] PARGOLAS OR FRAMING TO BE COVERED BY CLIMBING PLANTS. PRIVACY IS NOT OBTAINED FOR PRIVACY - PALING FENCES - SCREEN WALLS DO NOT PERMIT DIRECT VIEW BUT ALLOW BREEZE TO PENETRATE EG. LOUVERS. THE DENSITY OF HOT-DRY IS MORE THAN WARM-HUMID REGIONS. THREE REASONS TO ALLOW FREE MOVEMENT OF AIR THROUGH BUILDINGS AND SPACES BETWEEN BUILDINGS. TO PROVIDE PRIVACY BY DISTANCES,AS WALLS AND SCREENS CANNOT BE USED FOR THIS PURPOSE. MANY ACTIVITIES ARE CARRIED OUT-OF-DOOR.

22 External space Hot-dry climate

23 External space Hot-dry climate

24 External space Hot-dry climate

25 ROOFS, WALLS AND OPENING Hot dry climate In hot dry climate roof and walls would absorb more heat during day time due to heavy material. Thus the design of opening is governed by two requirements: 1.During the day the absence of opening would be most desirable, or at least opening as small as possible, located high on the walls. 2. During the night the openings should be large enough to provide adequate ventilation for the dissipation of heat emitted by the walls and roofs. Designer must study the occupancy pattern of the building. For eg., - office building must have time lag of 4-6 hours. - residential building must have time lag of 9-12 hours. In regions where diurnal ranges are less extreme,where the night-time temperature does not fall below the comfort zone, the large thermal capacity should be restricted to internal walls, partition and floors, whilst the outer walls and roof would need to have a high resistive insulation. Alternatively separate day and night rooms could be provided in the house.

26 ROOFS, WALLS AND OPENING Hot dry climate

27 ROOFS, WALLS AND OPENING Hot dry climate

28 WARM-HUMID CLIMATE THE CONSTRUCTION OF BUILDING OF LOW THERMAL CAPACITY MATERIAL OF LIGHT WEIGHT IS ADVISABLE. ROOFS AND WALLS THE ROOF IS PRACTICALLY THE ONLY ELEMENT WHICH HAS A VERY GREAT SIGNIFICANCE. IT CANNOT IMPROVE THE CONDITIONS, I.E., IT WILL NOT PRODUCE TEMPERATURES COOLER THAN THE OUT DOOR AIR, BUT ATLEAST, IF WELL DESIGNED,IT CAN PREVENT THE INDOOR TEMPERATURE INCREASING ABOVE THE OUT DOOR AIR TEMPERATURE, AND KEEP THE CEILING TEMPERATURE AROUND THE SAME LEVEL AS OTHER SURFACES. IT HAS BEEN SUGGESTED (97) AS A PERFORMANCE STANDARD, THAT RHE CEILING TEMPERATURE SHOULD NOT EXCEED THE AIR TEMPERATURE BY MORE THAN 4 C.

29 ROOFS AND WALLS WARM-HUMID CLIMATE

30 ROOF AND WALL SURFACES HOT - DRY CLIMATE IT DEPENDS UPON : 1. SURFACE MATERIAL 2. SURFACE TREATMENT 3. COLOUR CONTROLS THERMAL BEHAVIOUR AND PREVENTS HEAT RADITAION COLOUR USED MUST BE LIGHT THE MATERIAL USED SHOULD BE SHINY REFLECTS LARGE AMOUNT OF INCIDENT RADIATION ROOF ANY LOCATION NEAR THE EQUATOR RECIEVES GREATEST AMOUNT OF SOLAR RADIATION DURING DAY TIME DURING NIGHT IT IS MOSTLY EXPOSED, THUS IT EMITS RADIATION TO OUTER SPACES. ROOF SUFRACES MATTER MORE THAN THE WALL SURFACES. ABSORBANCE AND EMITTANCE VALUE REMAIN SAME FOR A MATERIAL FOR SAME TEMPERATURE.

31 ROOF AND WALL SURFACES HOT - DRY CLIMATE

32 ROOF AND WALLSURFACES WARM-HUMID CLIMATE OPENINGS MUST BE PLACED SUITABLY IN RELATION TO THE PREVAILING BREEZES TO PERMIT NATURAL AIR FLOW THROUGH THE INTERNAL SPACES AT BODY LEVEL. SUCH OPENINGS SHOULD BE LARGE AND FULLY OPENABLE; THERE IS NO POINT IN HAVING FIXED GLASS PANES. OPENINGS SHOULD BE FROM THE EFFECT OF OUTSIDE OBSTRUCTIONS. AIR FLOW SHOULD NOT PASS OVER HOT SURFACES BEFORE REACHING THE BUILDING. LARGE OPENINGS GIVEN PROTECTION DRIVING RAIN,INSECTS,SMELLS AND NOISE WITHOUT RADICALLY REDUCING AIR MOVEMENT. CEILING MOUNTED OR OTHER ELECTRIC FANS MAY BE USED WHEN THERE IS LITTLE OR NO BREEZE,BUT THESE WILL NORMALLY PROVIDE AN AIR MOVEMENT,NOT INDUCE THE EXCHANGE OF AIR.

33 VENTILATION AND AIR FLOW HOT - DRY CLIMATE DURING THE DAY-TIME OPENINGS SHOULD BE CLOSED AND SHADED. AS THE HOTTEST SURFACE IS LIKELY TO BE THE CEILING OR THE UNDESIRABLE OF THE ROOF, IT IS ADVISSABLE TO HAVE THE TOP OF THE OPENINGS LEVEL WITH THE CEILING. ATTENTION MUST BE PAID TO THE DESIGN OF THE OPENINGS TO THIS SPACE AND THEIR ORIENTATION IN RELATION TO THE PREVAILING BREEZE. ROOF SLOPES SHOULD BE ORIENTED TOWARDS THE PREVAILING BREEZE, AND ANY OBSTRUCTIONS WHICH WOULD PREVENT THE AIR FLOW NEXT TO THE ROOF SURFACES SHOULD BE AVOIDED. HIGH SOLID PARAPET WALLS AROUND THE ROOF WOULD, CREATE A STAGNANT POOL OF HOT AIR, AND SHOULD THEREFORE BE AVOIDED.

34 VENTILATION AND AIR FLOW HOT - DRY CLIMATE

35 VENTILATION WARM-HUMID CLIMATE WITHOUT THE EXCHANGE OF AIR BOTH THE TEMP. AND THE HUMIDITY OF ROOM AIR WILL INCREASE ABOVE THE OUT DOOR VALUES, DUE TO THE HEAT AND MOISTURE OUTPUT OF HUMAN BODIES AND OSF VARIOUS HUMAN ACTIVITIES (EG WASHING NAND COOKING) IN THIS CLIMATE THERE IS A NEED FOR BOTH VENTILATION AND FOR A SENSIBLE AIR MOVEMENT ACROSS THE BODY SURFACE. CARE MUST BE TAKEN TO AVOID AIR WHICH HAS PASSED THROUGH A ROOF SPACED REACHING THE LIVING ZONE(EG. VERANDAH) AS THIS WILL BE MUCH HOTTER THAN THE NORMAL OUTDOOR AIR

36 VENTILATION WARM-HUMID CLIMATE

37 TRADITIONAL SHELTER HOT - DRY CLIMATE DESERT REGION SHELTER HEAVY WALLS OF EARTH,BRICK,STONE AND ROOFS ARE OF SAME MATERIALS. THICK WALLS PROVIDES GOOD THERMAL CAPACITY SECURITY PROTECTION AGAINST NOISE STRUCTURES TENDS TO BE HOT AT NIGHT DURING HOT SEASONS. PREVENTION OUTER PRIVATE SPACES SUCH AS COURTYARDS AND ROOFS ROOMS BUILT AROUND A CENTRAL COURTYARD WHICH PROVIDES COOLER ATMOSPHERE AT NIGHT. WINDOW DOORS ARE SMALL IN SIZE AND LESS IN NUMBER. WINDOWS LOCATED HIGH ON WALLS. ADMITTING LESS HEAT AND DUST, REDUCING GROUND GLARE. VENTILATIONS ARE INADEQUATE AND ALSO THE HOUSES ARE CLOSELY BUILT.

38 TRADITIONAL SheLTER WARM- HUMID CLIMATE BASICALLY TWO TYPES OF SHELTER EARTH POOR AND NON-INTENSIVE AIR CREATES UNBEARABLE CONDITION. INTENSE HEAVY RAIN ERODE THE BASES AND SURFACES OF EARTH WALLS. ANNUAL MAINTAINANCE IS ESSENTIAL. UNVENTILATED INTERIOR REMAIN CONSTANTLY DAMP. TIMBER SHELTER IS ELEVATED BY STILTS LOCAL TIMBER AND BAMBOO IS USED. THATCH COVERS BAMBOO ROOF- FRAME WITH OVERHANGING EAVES. THATCH IS BETTER THERMAL INSULATOR. THATCH ROOF IS CONVENIENT TO THE BREEDING OF INSECTS AND TERMITES. LIGHTWEIGHT TIMBER HOLDS LESS HEAT AND COLS ADEQUATELY AT NIGHT ELEVATED SHELTER BROAD EAVES SHADE THE WALLS AND OPENING, PROVIDE PROTECTION FROM DRIVING RAIN AND SKY GLARE AND PERMIT THE OPENING TO BE KEPT OPEN MOST OF THE TIME.

39 MARITIME DESERT CLIMATES HOT-DRY CLIMATE THESE CLIMATES DIFFER ONLY SLIGHTLY FROM THE HOT DRY DESERT REGIONS - THE MAIN DIFFERENCE BEING THE HIGH HUMIDITY. THE COASTAL WIND BLOWING OF THE SEA DURING THE DAY MAY BE UTILISED FOR BETTER THERMAL CONDITIONS. THE NIGHT TIME WIND BLOWING TOWARDS THE SEA, BRINGS THE HOT INLAND DESERT AIR, POSSIBLY DUST,AND IT CAN BE DECIDEDLY UNPLEASANT. THE ONLY SOLUTION TO PROVIDE A) ONE WITH HIGH THERMAL CAPACITY WALLS AND ROOFS, FOR USE AT NIGHT,ESPECIALLY DURING THE COOLER PART OF THE YEAR. THIS SHOULD HAVE NO OPENINGS FACING THE INLAND DIRECTION. B) ONE OF LIGHT WEIGHT CONSTRUCTION, THE ROOF ONLY TO PROVIDE SHADE, THE SIDE FACING THE SEA, AS WELL AS THE OPPOSITE SIDE BEING ALMOST COMPLETELY OPEN. THIS IS THE BEST SOLUTION FOR DAY TIME USE, ESPECIALLY DURING THE HOTTEST PART OF THE YEAR.

40 MARITIME DESERT CLIMATES HOT-DRY CLIMATE

41 Warm-humid island climate WARM-HUMID CLIMATE TEMPERATURES ARE SLIGHTLY LOWER, BUT THERE IS A STEADY WIND OF 6-7 M/S AND ALMOST CONSTANT DIRECTION TO RELY ON FOR COOLING. THE ORIENTATION AND CONSTRUCTION OF THE BUILDING TO CATCH THE MAXIMUM AMOUNT OF AIR MOVEMENT WILL BE EVEN MORE IMPERATIVE THAN IN WARM-HUMID CLIMATE. MOST OF THESE ISLANDS LIE IN THE TROPICAL CYCLONE BELT. CONSTRUCTION AND STRUCTURE MUST BE DESIGNED TO WITHSTAND THE WINDS OF UPTO 7O M/S.

42 Warm-humid island climate WARM-HUMID CLIMATE

43 climate Common factors

44 SHIVAM PATEL 12SA131 VAIBHAVI LUHANA 12SA139 MEET PATEL 11SA120 SHIVANI PATEL 12SA132 SWAPNIL PATEL 12SA137 RAHUL MAKWANA 12SA128