climate study of warm and humid climate in india - Panaji,goa

1. CLIMATE ANALYSIS
Warm and Humid Climate
City : Panaji, Goa
Building type: Hotel
SUBMITTED BY- PRACHI PANDEY

2. Climate Data for Panjim, Goa
TEMPERATURE AND PRECIPITATION
Source: climate-data.org
 The temperatures are highest on average in May, at around 30.2 °C | 86.4 °F. At 25.9 °C | 78.6 °F on
average, January is the coldest month of the year.
 The least amount of rainfall occurs in January. In July, the precipitation reaches its peak, with an
average of 930 mm | 36.6 inch.
HUMIDITY
Source: Worlddata.info
 August is the most humid month in Panjim, India, with an average relative humidity of 89% and
December is the least humid month with an average relative humidity of 64% .

3. SUNSHINE HOURS
Source: Worlddata.info
 The month with most sunshine is February (10.4h). The month with least sunshine is July (3.4h).
 The month with the longest days is June (13h). The month with shortest days is December (11.2h)
CLOUD COVERS
Source: Climate Consultant
 The graph shows the monthly number of sunny, partly cloudy, overcast and precipitation days.
 Days with less than 20% cloud cover are considered as sunny, with 20-80% cloud cover as partly
cloudy.
 More than 80% as overcast.

4. SOLAR RADIATION
Direct Normal source: Climate Consultant
Global horizontal
Total surface
(wh/sqm per hour)
 Months with the highest UV index are March, April, May, June, July, August and September (UV index
12). The month with the lowest UV index is December
SUN PATH DAIGRAM
Source: Gaisma

5. WIND (SPEED AND DIRECTION)
Source: MeteoBlue
Source: WindFinder
TOPOGRAPHY
 The topography within 2 miles of Panaji contains only modest variations in elevation,
with a maximum elevation change of 240 feet and an average elevation above sea level
of 47 feet.
 The area within 2 miles of Panaji is covered by artificial surfaces (69%) and water (24%),
within 10 miles by water (43%) and cropland (23%), and within 50 miles by water (54%)
and trees (17%).

6. CLIMATE ANALYSIS OF PANAJI, GOA (source: Climate consultant)
 Bio climatic chart
 Psychometric chart
 Mahoney table
 Isopleth chart
BIO CLIMATIC CHART
source: Climate Consultant
Inferences using Bioclimatic chart of Gorakhpur
Day inferences Night inferences
Morning in the month of janurary requires some air
movement due to high temperature and the large
portion of the days fall in the comfort zone.
Day time require air movement all year round to
maintain the comfort zone.
Night are comfortable in the month of january and
may require some radiation to attain comfort.
Night time requires air movement all year round to
achieve comfortable habitat due to low
temperature and higher humidity.

7. Inferences from bio climatic chart
Month Comfort Radiation
needed
Shading
needed
Air movement
needed
Prevailing wind
directions
January 75% × 95% 20% 90-NW
February 60% × 100% 50% 0-WNW
March 60% × 100% × 320-W
April × × 100% 100% 320-W
May × × 100% 100% 320-WNW
June × × 100% 100% 270-WSW
July × × 100% 100% 270-W
August × × 100% 90% 270-W
September × × 100% 90% 320-W
October × × 100% 90% 0-W
November × 25% 100% 100% 50-N
December × 50% 100% 60% 90-NNE
PSYCHROMETRIC CHART
source: Climate Consultant

8. Conclusion from Psychrometric Chart:
January 27 % Requires sunshading on windows during day.
8.7 % Ventilation during night is required; night flushing is required.
32% Adaptive comfort ventilation is required
23% Cooling and dehumidification required; removal of water from air as air
temperature falls beloew dew point temperature.
February 30 % Requires sunshading on windows during day.
8 % Ventilation during night is required; night flushing is required.
39% Adaptive comfort ventilation is required
27% Cooling and dehumidification required.
March 30 % Requires sunshading on windows during day.
55% Adaptive comfort ventilation is required
37% Cooling and dehumidification required.
April 30 % Requires sunshading on windows during day.
55% Adaptive comfort ventilation is required
38% Cooling and dehumidification required.
May 31 % Requires sunshading on windows during day.
48% Adaptive comfort ventilation is required
52% Cooling and dehumidification required.
June 27 % Requires sunshading on windows during day.
78% Adaptive comfort ventilation is required
21% Cooling and dehumidification required.
July 29 % Requires sunshading on windows during day.
81% Adaptive comfort ventilation is required
15% Cooling and dehumidification required.
August 28 % Requires sunshading on windows during day.
88% Adaptive comfort ventilation is required
10% Cooling and dehumidification required.
September 28 % Requires sunshading on windows during day.
75% Adaptive comfort ventilation is required
23% Cooling and dehumidification required.
October 25 % Requires sunshading on windows during day.
60% Adaptive comfort ventilation is required
32% Cooling and dehumidification required.
November 25 % Requires sunshading on windows during day.
61% Adaptive comfort ventilation is required
28% Cooling and dehumidification required.
December 27 % Requires sunshading on windows during day.
40% Adaptive comfort ventilation is required
28% Cooling and dehumidification required.
24% Dehumidfication only.

9. ISOPLETH CHART
source: Climate Consultant

10. MAHONEY TABLE

11. DESIGN RECOMMENDATION

12. Conclusion from Mahoney Table
Layout: Long axis east-west Orientation north and south.
Spacing: Open spacing protection from winds.
Air movement: Single banking; permanent required
Size of openings: Medium: 25-40%
Position of openings: In North and South walls at body height.
Protection of openings: Protection from rain and sunlight
Walls and Floors: Heavy,over 8hours long time lag
Roofs : Light and well insulated
Outdoor sleeping: No provision of outdoor sleeping required.
RAin protection: Provide adequete rain water drainage.
PASSIVE DESIGN STRATEGIES:
 Natural cross ventilation to take advantage of air velocity in getting comfort,maximise
air movement.
 Minimise solar incidence (size, location and type)
 Temperature at the interior level can be maintained by the proper designing of
ventilation and utilisation of air movement at increased velocity, which takes the
advantage of reduction in heat and compresses the humidity level.
 The main elevations and rooms should be placed facing north and south and towards
the prevailing wind.

13. SUN ORIENTATION
 Orientation of the settlements pattern should be placed preferably on southern or
northern slopes.
 The best orientation is longer sides facing north and south directions to protect from
the solar radiations.
 the east and west sides should be shaded by shading devices.
WIND ORIENTATION
 Ideal sites are windward slopes near the crest or near the beach, where regular winds
exist.The ventilation effect of winds can be improved by effective arrangement of
vegetation.
 Elongating the settlement in a line across the prevailing wind direction gives low
resistance to air movement and is therefore the ideal solution.
 Cross-ventilation acts more effective in interior spaces by enlarging the openings of the
internal partitions and by providing free passage, courtyards, verandah, etc.
 Oblique winds between 30 and 120 degrees to the wall can also provide
cross-ventilation. This can be intensified by some vegation wich provide shade and
deflection.
 The attic spaces can also be used for ventilation, it helps to decrease the solar heating
through the roof.


14.  Continuous circulation of air enhances the space with appropriate temperature and
humidity
Courtyard effect and evaporative cooling
URBAN FORMS AND EXTERNAL SPACES
 In order to take the advantage of air circulation, an open settlement pattern is
preferred.
 This pattern enhances the airflow thus facilitating proper ventilation.
 Linear streetscapes are more advantageous for uninterrupted air movement.
FORM AND ORIENTATION
 The shape of a building affects the ventilation.
 Large surface areas are preferred to compact buildings. This favours ventilation and
heat emission at nighttime.
 Two or three floors are recommended as taller buildings have too much radiant heat
and also obstruct air flow to neighbouring buildings.
 Reduction of direct heat gain by radiation through openings and of the internal surface
temperature.

15. OPENING AND SHADING DEVICES
 To increase the cross-ventilation large openings can be designed. However, in that case
solar radiation can penatre directly into the interior of the building if they are not
correctly shaded.
 If the windows are unshaded, the glass area has to be limited to 15% of the facade area.
An increase of the glass area to 30% will increase the room cooling power needed by
30%-50% and facades to the west are most affected.
 Shading devices provided should be much larger as the radiation is diffused, provided it
obstructs the sky and not just the sun.
Adjustable and Movable types of louvers

16. SURROUNDINGS AND VEGETATION
 A low cost solution for creating a shading device is by providing vegetation rich
environment, creating a micro climate. They are designed in such a way that it does not
hinder the air movement.
 Another efficient solution is to grow a green cover over roofs and walls. This cover
functions as a second skin which provides
• protection against solar radiant heat,
• cooling by a ventilated space between green cover and wall or roof,
• reduction of glare,
• reduction of noise, by sound absorption,
• reduction of dust, by filtering the air,
• stabilization of the microclimate,
• protection of the wall and roof surfaces from wind and driving rain,
• a regulating effect on humidity

17. BUILDING ENVELOPE
ROOF
 The main purpose of a roof is to protect against rain. It is also used to decrease the heat
gain in the building in two ways: removing the solar heat gain by ventilation of the roof
and by thermal insulation of the roof.
 The roof colors must be bright or white to decrease the solar heat gain.
 In addition to provide shelter from rain and heat, the form of roof should be planned to
promote air flow.
 Vents at the rooftop effectively induce ventilation and draw hot air out.
 A double roof with a ventilated space in between can also be used to promote air
flow.
WALLS
 The walls must also be designed to promote airflow 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.
 Thermal performance of walls can be improved by following ways:
1. Increasing wall thickness
2. Providing air cavity between walls and hollow masonry blocks
3. Applying insulation on the external surface.
4. Applying light coloured distemper on the exposed side of the wall.

18. MATERIALS
 In warm-humid climate building materials are deteriorated rapidly.Concrete is a good
material for permanent structures in the tropics.
 A solution can be to use a low water-cement ratio, maximum 0,6.
 Wood can be used for several functions if it is installed properly. A wood structure must
be designed so wooden parts can be easily replaced and have to be treated against rot,
mould and termites.
 All organic materials placed against masonry or concrete need a vapour barrier between
the materials. Such as the roof, walls must be painted in a bright color.
ACTIVE DESIGN STRATEGIES:
Active design is referred to mechanical and technological solutions. The active design
strategies include electric and thermal energy generation (photovoltaic panels, wind
turbines, thermosyphons etc.), movable sun protection, active cooling (solar assisted or
conventional HVAC), artificial lighting and mechanical ventilation.

19. VERNACULAR ARCHITECTURE:
Vernacular architectures and solar passive features in warm and humid climatic zone:
(A) approach and open space in front of the building,
(B) Chajja and extended roof.
(C) window overhang,
(D) adobe house construction,
(E) structure in veranda to block afternoon sun from entering in the rooms
(F) window blind made up of wood and selectively operable, and
(G) air gap in ceiling.
Goan Houses
The Goan houses of the past used environment friendly building materials. These wooden
roofs, thick mud & Laterite walls, cow dung & mud plaster for flooring & clay tiles held very
little heat & cooled the whole house.
Natural resources (materials) as building materials.
Wood – for roof, doors, windows, furniture, false ceiling.
Mud – for walls, floorings.
Local Laterite stones – for walls, compound walls, flooring..
Clay tiles – for flooring, roofing.
Vegetable and natural dyes – for coloring.
Oyster shells (mother of pearl shell) – for windows shutters.
Thick grass, bamboo and palm frond mats – for window shades and awnings.
Basalt or granite – flooring, Walls.

20. Resources for conducive environment:
Air movement–Houses were randomly arranged, this because the velocities of the passing
wind to be considerably reduced while allowing for air circulation.
House clustering with divided commnon space due to contour land topography and flatter
land topography
Tall fruit trees–Tall fruit tree like the coconut, mango & jackfruit were often planted in
front garden to provide shade as well as allow the passage of wind abundant oxygen.
Breeze from the sea– Another factor that contributed to the comfort of houses was the
high plinth with the comfort of houses captured the breeze from the sea & also protected
the house from the raising damp during & after monsoon as well as offered house – owners
the added benefit of a vantage point.

21. Grass, bamboo & palm frond mats– Shady & cool living spaces are of paramount
importance in a tropical & humid climate. In each of these spaces, devices that filter direct
sunlight while allowing air circulation were essential. These devices in Goa have always
been palm front matting fashioned into window shades & awnings. They used palm frond
matting on the sides of the balcao & the veranda
Landscape - The front landscape (garden) acts as a buffer the house & the road & because
of plants / trees / shrubs in the garden, the lower half of the house is partially concealed
behind all this foliage. The garden helps in affording a certain degree of privacy in balco or
veranda. Fruit trees – guavas, papayas, chiku, jackfruit & mango were planted in gardens in
backyards.
Laterite - it is still a sensible material to use- as it does not uses any industrial processing,
does not need to be transported great distance, is labour intensive in its extraction and
encourages the local economy.
Comfort enhancing resources -
The long veranda around the façade is designed to keep out the rain. A veranda stretches
around the whole of façade, the veranda both very wide and very long was a favorite spot
for relaxing and also served to aerate the house.
The wide shaded verandas girdling the centralcourt yard.

22. The vasary(veranda) was parallel to the façade and opening onto the interior patio linked
the social and domestic parts of the houses. Balcao used as a small gathering space in front
of the house.