Bioclimatic Analysis

Bioclimatic Analysis of the house in Mallar village (Udupi district,Karnataka)

Divya D D

Contents 1

Introduction- ............................................................................................................................. 6

2

Aim-........................................................................................................................................... 6

3

Objectives- ................................................................................................................................ 6

4

Methodology- ............................................................................................................................ 6

5

Introduction to the city-Kaup,Udupi district Manipal ................................................................. 7 Regional Setting of the Kaup City ............................................................................................... 7 Origin (Historical Background of the Kaup City) .............................................................................. 7 Geographical and Social History ................................................................................................. 7

6

General Architectural characteristic of the place. ....................................................................... 9

7

Location of the site .................................................................................................................. 11

8

Climate .................................................................................................................................... 13 8.1

Temperature and precipitation ........................................................................................ 14

8.2

Humidity .......................................................................................................................... 18

9

Introduction to the house, Occupants, and spatial attributes. .................................................. 20 9.1

Plan.................................................................................................................................. 20

9.2

Architecture ..................................................................................................................... 21

9.2.1

Roof- ........................................................................................................................ 21

9.2.2

Wall.......................................................................................................................... 21

9.2.3

Floor......................................................................................................................... 21

9.2.4

Winows .................................................................................................................... 21

9.3

Anthropology- .................................................................................................................. 22

9.3.1 10

Understanding the Activities of manufacturing sarees with relation to the rooms .... 24

Sun path diagram(analysising direct beam radiation) ........................................................... 29

10.1

Observation for various months at 12pm. ........................................................................ 29

10.2

Analysis of the sun path movement during a day ............................................................. 35

10.3 Observation and inference from other design elements with respect to sun path and activities ...................................................................................................................................... 37 11

Wind movement and humidity control. ................................................................................ 40

11.1

Humidity,wind and its relation to the temperature. ......................................................... 41

11.2

Inference.......................................................................................................................... 42

12

Thermal mass and its relation to the materials used. ........................................................... 43

12.1

Understanding thermal mass of the walls and its contribution for the internal heat gain. . 45

12.2

Calculating thermal mass of the roof ................................................................................ 46

12.3

Heat flux calculation for west wall .................................................................................... 47

12.4

Inference.......................................................................................................................... 49

13

Sun light hours ..................................................................................................................... 50

13.1 14

Total surface radiation of wall .......................................................................................... 52 Psychometric chart .............................................................................................................. 53

14.1

Design for overhangs for this climate. .............................................................................. 54

14.1.1

Design of overhangs between December to june. ..................................................... 54

14.1.2

Design of overhangs between june to December. ..................................................... 54

15

Design strategies.................................................................................................................. 55

16

Design strategies to be worked on ....................................................................................... 62

Figure 1beach on the western side .................................................................................................... 8 Figure 2 ............................................................................................................................................. 8 Figure 3 Pattern of increase in built up area in Kaup from 2004 to 2018 ............................................ 8 Figure 4 ............................................................................................................................................. 9 Figure 5 ............................................................................................................................................. 9 Figure 6 ........................................................................................................................................... 10 Figure 7 ........................................................................................................................................... 10 Figure 8 Climate category ................................................................................................................ 13 Figure 9 Average temperature and precipitation ............................................................................. 14 Figure 10 ......................................................................................................................................... 14 Figure 11 Udupi weather by month ................................................................................................. 15 Figure 12 Temperature variation ..................................................................................................... 15 Figure 13 ......................................................................................................................................... 16 Figure 14 ......................................................................................................................................... 17 Figure 15 ......................................................................................................................................... 17 Figure 16 ......................................................................................................................................... 18 Figure 17 humidity comfort level ..................................................................................................... 18 Figure 18 ......................................................................................................................................... 19 Figure 19 plan.................................................................................................................................. 20 Figure 20 Red oxide flooring ............................................................................................................ 20 Figure 21 Mangalore tiles ................................................................................................................ 20 Figure 22 brikck walls ...................................................................................................................... 20 Figure 23 Section A-A ...................................................................................................................... 21 Figure 24 kitchen ............................................................................................................................. 22 Figure 25 Room 2 western side ........................................................................................................ 22 Figure 26 ......................................................................................................................................... 22

Figure 27 ......................................................................................................................................... 22 Figure 28 Door-wooden ................................................................................................................... 23 Figure 29 ......................................................................................................................................... 23 Figure 30 ......................................................................................................................................... 23 Figure 31 ......................................................................................................................................... 23 Figure 32 ......................................................................................................................................... 23 Figure 33 ......................................................................................................................................... 23 Figure 34 ......................................................................................................................................... 23 Figure 35 ......................................................................................................................................... 23 Figure 36 only a representation pic (not from the house) ................................................................ 24 Figure 37 weaving ........................................................................................................................... 25 Figure 38 ......................................................................................................................................... 25 Figure 39 ......................................................................................................................................... 26 Figure 40 ......................................................................................................................................... 28 Figure 41 ......................................................................................................................................... 28 Figure 42 sun path movement ......................................................................................................... 29 Figure 43 ......................................................................................................................................... 30 Figure 44 ......................................................................................................................................... 30 Figure 45 ......................................................................................................................................... 31 Figure 46 December 22st ................................................................................................................. 31 Figure 47 ......................................................................................................................................... 31 Figure 48 ......................................................................................................................................... 32 Figure 49 ......................................................................................................................................... 32 Figure 50 ......................................................................................................................................... 32 Figure 51 ......................................................................................................................................... 33 Figure 52 ......................................................................................................................................... 33 Figure 53 ......................................................................................................................................... 33 Figure 54 ......................................................................................................................................... 34 Figure 55 ......................................................................................................................................... 34 Figure 56 ......................................................................................................................................... 34 Figure 57 7 35am ............................................................................................................................. 35 Figure 58 6:20am. ............................................................................................................................ 35 Figure 59 4:35pm ............................................................................................................................ 36 Figure 60 6pm ................................................................................................................................. 36 Figure 61 ......................................................................................................................................... 37 Figure 62 ......................................................................................................................................... 38 Figure 63 ......................................................................................................................................... 40 Figure 64 ......................................................................................................................................... 40 Figure 65 ......................................................................................................................................... 40 Figure 66 ......................................................................................................................................... 40 Figure 67 April ................................................................................................................................. 41 Figure 68 ......................................................................................................................................... 42 Figure 69 East wall properties.......................................................................................................... 43 Figure 70 north wall properties ....................................................................................................... 43 Figure 71 west wall properties ......................................................................................................... 44

Figure 72 South wall properties ....................................................................................................... 44 Figure 73 ......................................................................................................................................... 46 Figure 74 south roof ........................................................................................................................ 47 Figure 75 April 19th at 7pm ............................................................................................................. 48 Figure 76 April 19th 12pm .............................................................................................................. 48 Figure 77 West wall total radiation .................................................................................................. 52 Figure 78 South wall total radiation ................................................................................................. 52 Figure 79 north wall ........................................................................................................................ 52 Figure 80 East wall ........................................................................................................................... 52 Figure 81 ......................................................................................................................................... 54 Figure 82 ......................................................................................................................................... 55 Figure 83 ......................................................................................................................................... 55 Figure 84 ......................................................................................................................................... 56 Figure 85 ......................................................................................................................................... 56 Figure 86 ......................................................................................................................................... 57 Figure 87 ......................................................................................................................................... 57 Figure 88 ......................................................................................................................................... 58 Figure 89 ......................................................................................................................................... 58 Figure 90 ......................................................................................................................................... 59 Figure 91 ......................................................................................................................................... 59

1 IntroductionThis is the study carry out as a part of course carried out by Varun thautam.A case study of a kaup house was taken to analyze the concepts thought during the course.

2 AimTo understand the bioclimatic aspects and its relation to the space design

3 Objectives

Climatic data, plotting and analysis



Investigating the relationship of the building with the movement of the sun.



perception of thermal qualities (using vernacular architecture as a lens)Delight, Affection and Sacredness.



Thermal mass calculation



Representation of the comfort zone for your climate



Understanding humidity and its relation to space design.

4 MethodologyObservatory analysis and use of softwares to analyze and interpret the bioclimatic aspects

5 Introduction to the city-Kaup,Udupi district Manipal Udupi district-Stretching around It is situated 58km to the north of Mangalore at an altitude of 10m above the mean sea level. It is flanked by Arabian Sea towards the east, Western Ghats in the west, Swarna River towards the north and river Udyavara to the south.Today it is observed that there is a shift from that of the joint family to nuclear family housing. The land is highly contoured on the eastern edge and the land is penetrated by water in the form of rivers, streams, rivulets and natural drains which need special attention. The predominant land use is agricultural fields however the residential outgrowth is slowly spreading along the main roads both in east-west and north-south direction.

Regional Setting of the Kaup City



Settled in between Mangalore and Udupi along the NH-66 Highway and costal area



Topography:



Costal Line: 13 Km



Surface Water Bodies: 158.25



Beach: Kaup Lighthouse Beach, Mattu Beach



Soil Type: Red lateritic and coastal alluvial



Annual Rainfall: 3011-4694mm

Origin (Historical Background of the Kaup City) 

There is historical clues that Tipu Sultan (1750-1799) invaded this area at certain period, as elders point out that a dilapidated fort near Kaup light house belonged to his period.



There are also clues of existence of a secret tunnel from this fort area upto Mallar village. During British era and even after the Indian Independence much of this area was under the control of Jain and lords.

Geographical and Social History



It is an interesting piece of history that how the name Kaup came.



Historians say that Kaup was known in the distant past as "Rakshanapura" The word Rakshane meaning “Potection" in Kannada language, translated into local Tulu language as Kaup that is 'Land of protection'(Land that protects).

The settlement in Kaup in the early times started near the coast due to the fishing activities. Figure 1 shows the development trend in Kaup. Agriculture is practiced on the coastal flatlands. Urban fabric away from the coast is sparsely developed due to the practice of agriculture.

The National Highway being the main link for connectivity, further development was seen along the highway along with the emergence of improved connectivity to the surrounding areas. The urban form is transformed from vernacular to contemporary while gradually directed away from the coast.

The future growth of the urban fabric may continue towards the undulating hills and valleys due to the connectivity factor.

Figure 3 Pattern of increase in built up area in Kaup from 2004 to 2018

Figure 2

Figure 1beach on the western side

6 General Architectural characteristic of the place.

Climate and its relation to architecture character. 

Courtyards

are

often

used

in

traditional

architecture to aid ventilation and day lighting. 

Locally available materials like mangalore tiles

,laterite stones and granite are used in construction.You would see the deep overhangs and chajja projections as a protective members against heavy rain and suns radiation. 

Open verandahs on all sides permit an even larger

overhang so that the walls are almost always in deep shade. 

Courtyards

are

often

used

in

traditional

architecture to aid ventilation and day lighting. 

Figure on the left shows the plan of the traditional

house. The overall plan of the building is rectangular in nature. The truth stone marks the entrance of the building as a stepping stone. There are two rows of columned space which mark the dominant external space. The grand Figure 4

entrance to the courtyard and the columned space is a community open space which marks the introvert planning considerations along with cross ventilation. 

Double floor height composed of granite and laterite

that is further extended into the verandah and staggers into two levels depending upon the location. This design feature is an efficient contributor in cooling the surface of the building.

The massive walls finished with brick, jaggery and straw act as efficient thermal insulators. Also the mud walls on the outside continue to hold out against the fierce rains that lash the region for more than four months at a stretch every year.

Ref- http://www.itpi.org.in/uploads/journalfiles/oct6_10.pdf Figure 5

Figure 7

Culture definitely has a role in how these street structure has taken shape. The cultural celebration being the part of temple festival activates certain streets.

On the outskirts the streets have organically grown ,with agriculture being the main practice.

Figure 6

7 Location of the site The house taken for study is located in the village of mallar.

The sitetaken for study falls under the Tropical monsoon Climate(Am),according to the koppen system.

Tropical monsoon and trade-wind littoral climate, Major climate type of the KĂśppen classification characterized by small annual temperature ranges, high temperatures, and plentiful precipitation (often more than wet equatorial, or Af, climates in annual total). Despite their resemblance to wet equatorial climates, tropical monsoon and tradewind littoral climates exhibit a short dry season, usually in the low-sun (“winterâ€?) season, and the highest temperatures generally occur at the end of this clear spell.

8 Climate

Figure 8 Climate category

The climatic date of udupi has been taken for reference,as the place of study is 30km away from udupi.

The Udupi lies on 9m above sea level The climate here is tropical. There is significant rainfall in most months of the year. The short dry season has little effect on the overall climate. This climate is considered to be Am according to the Köppen-Geiger climate classification. In Udupi, the average annual temperature is 27.2 °C | 80.9 °F. Precipitation here is about 4360 mm | 171.7 inch per year .

8.1 Temperature and precipitation

Figure 9 Average temperature and precipitation

Figure 10

April is the warmest month of the year. The temperature in April averages 29.4 °C | 84.9 °F. July has the lowest average temperature of the year. It is 26.0 °C | 78.8 °F. From the above graph it is observed that The hot season lasts for 2.3 months, from March 11 to May 22, with an average daily high temperature above 91°F. The hottest day of the year is April 19, with an average high of 93°F and low of 79°F. The cool season lasts for 2.7 months, from June 18 to September 9, with an average daily high temperature below 85°F. The coldest day of the year is January 15, with an average low of 72°F and high of 89°F.

Figure 11 Udupi weather by month

Figure 12 Temperature variation

From the above graph fig 3 and 4,it is observed that daily range of change in high to low temperature (diurnal range) is relatively high as compared to annual difference of high temperature to that of lowest temperature. It is observed that the diurnal difference is the highest in the months of January to march , when the highest mean temperature is 340C, and the mean low temperature is 200C. The diurnal difference is the lowest in the month between june to august,the highest mean temperature during day being 270C and the lowest mean temperature during night being 230C. The difference between the highest and lowest annual daytime temperature is 50C, and the difference between the highest and lowest night temperature is 30C(as seen in the fig3 and 4),which is relatively less as compared to the diurnal difference. Hence it is important to give importance to the thermal mass of the built structure, so that the wall shall act as a medium to store heat during the day and release heat during the night when the temperature turns very cold.

Figure 13

The predominant average hourly wind direction in Udipi varies throughout the year.

The wind is most often from the north for 1.5 months, from January 6 to February 21, with a peak percentage of 43% on February 15. The wind is most often from the west for 8.4 months, from February 21 to November 2, with a peak percentage of 99% on July 27. The wind is most often from the east for 2.1 months, from November 2 to January 6, with a peak percentage of 42% on January 1.

Figure 14

Figure 15

The average hourly wind speed in Udupi experiences significant seasonal variation over the course of the year.

The windier part of the year lasts for 3.5 months, from May 23 to September 9 , with average wind speeds of more than 8.5 miles per hour. The windiest day of the year is June 30, with an average hourly wind speed of 11.8 miles per hour.

The calmer time of year lasts for 8.5 months, from September 9 to May 23. The calmest day of the year is November 6, with an average hourly wind speed of 5.1 miles per hour.

8.2 Humidity

Figure 17 humidity comfort level

Figure 16

Figure 18

Udipi experiences significant seasonal variation in the perceived humidity.

The muggier period of the year lasts for 10 months, from January 28 to December 5, during which time the comfort level is muggy, oppressive, or miserable at least 75% of the time. The muggiest day of the year is July 23, with muggy conditions 100% of the time.

The least muggy day of the year is December 31, with muggy conditions 67% of the time.

It is observed that the humidity level in the atmosphere is lot more than the desirable humidity level almost through out the year.The humidity reaches as high as 90percent during the monsoon and 70 percent during the summer.Its only during December end to February the relative humidity reaches the comfortable level between 40 to 60 percent. Hence humidity control measures turns very important in the design of buildings. Hence we often see in the traditional vernacular architecture long window overhangs and verandah.

9 Introduction to the house, Occupants, and spatial attributes.

This house was constructed 35yrs ago in the year 1984 for a lower-income family of 4 people, a mother, 2 daughters of 16 and 25 years old and a sun 15 yrs in age . The family belonging to padmashali caste mainly involved in weaving as occupation. The house was designed considering the space required to keep the weaving machine.

9.1 Plan

4

2

5

3

1

Figure 19 plan

Figure 22 brikck walls

Later addition to the house

Figure 21 Mangalore tiles

Figure 20 Red oxide flooring

9.2 Architecture As observed from the above plan the plan is oriented in the east-west direction, with the long sides facing north and south.

General Architectural characteristics 9.2.1 RoofSloping roof with Mangalore tiles being the prominent feature as the region receives heavy rainfall.Slope ranging between 150to 300.Mangalore tile is supported by rafters and purlins.

9.2.2 Wall The walls areconstructed of bricks done onsite. As the cost of bricks manufactured on site is comparatively less to that of normally used laterite onsite manufacture brick was used.The walls constructed has thickness equal to 2 brick size.(15+15=30cm).Cement plasters where used everywhere exept in the interiors where mud plaster was used.

9.2.3 Floor Red oxide floor is used .works as an emollient 9.2.4 Winows Windows constructed out of wood.Openings are very minimum.Opening size varying between 2’(W)x 2’8”(h) and 2’8”(w)x2’4”(h) 9.2.4.1 Doors Doors are made of wood and its size varying from 2’6”x5’4”(front door) and other doors being (2’6”x5’9”)

Figure 23 Section A-A

9.3 AnthropologyActivities in the house have been split into 2 category-

1. 30 years back when the house was constructed for the specific activities.

2. And the activities now The house was designed 36 years back for a low income family compirising of single mother (35)who was involved in the activities of weaving.Her 2 daughters of ages 17 and 25 and a son of 14 years of age.one of the daughter used to go to school and the other was involved in the activities of beedi making.

The later addition of the house is marked in red in the fig18.The activities then can be described as follows Mother used to wake up early and cook food in the kitchen located in the southern part of the house as shown in the figure.The cooking was carried out using the Chula.While the eldest daughter and the mother were at home carrying out their daily work , son was off to school. Room number 2 is the place where the activities pertaining to weaving used to take place during the day from8am to 5pm.Room number 1 and 3 being the later addition.

Room number 1 located on the northern side of the house was used during night for beedi making by the eldest daughter and also for loom preparation by the mother.Room number 3 was used for tailoring.

Today the rooms have been converted to different purpose as the weaving activities are not being carried out.Today the eldest daughters family recide in this house. So the house is currently occupied by a mother and her 2 sons of age 26 and 26 .Currently these 2 sons are the bread earners of the family.Previously the mother was involved in beedy making and their father used to cook and sell samosas in the nearby stall.Hence there was extensive use of chulha.

Figure 25 Room 2 western side

Figure 27

Figure 24 kitchen

Figure 26

Figure 35

Figure 28 Door-wooden Figure 34

Figure 33

Figure 29

Figure 32

Figure 31

Figure 30

9.3.1

Understanding the Activities of manufacturing sarees with relation to the rooms

9.3.1.1 Step 1-The Procurement Of Raw Materials & Verifying Their Usability Is The First & A Very Important Step The Process Starts With The Selection Of The Silk Yarn, Which Is Of Various Qualities & Imported From Various Production Centres. Raw Silk Is Specially Treated For Brocades & The Process Requires Considerable Patience & Labour The Cost Of Raw Materials Varies Depending Upon The Type Of Yarn 9.3.1.2 Step 2- Cotton yarns are giving colour bath for dying .(This was not being done in this house) Dyed yard are dried under the diffused sunlight for two days for oxidation, original colour and strength.Yarns are spun to the bobbins, these bobbins are arranged on custom made creels. Yarns are then spun on a large wooden frame. Wooden frame is turned anti clock-wise, to spin new set of threads. two set of threads are required in warp. Wooden comb is used to separate each individual thread and prevent friction among them.

9.3.1.3 Step 3-Loom Preparation Room marked 1 in the plan is the place where this activity happens. The warp threads are loaded onto the loom. Depending on the design, the warp threads are put through the appropriate shafts and heddles. The shafts and heddles lift some warp threads based on the design. The shafts are are vertical strings connected to a pattern controller that sits on top of the loom. During weaving the weft thread is passed in between the lifted and un-lifted warp threads thereby weaving the fabric according to the design. For double ikat, where both the warp and weft have patterns, the weaver has to manually adjust each weft thread to align the pattern.

Figure 36 only a representation pic (not from the house)

9.3.1.4 Step-4 Weaving The weaving process consists of pulling the shuttle between the raised warp threads. The weft thread is packed into the cloth using a series of vertical strings called the beater.

Figure 37 weaving

Ref- http://www.sarasu.in/The-Handloom-Weaving-Process-pid-405224.html 9.3.1.5 Other daily activities in the house.

Figure 38

9.3.1.6 Room no. 1(as shown in the plan) This is the same room where activity number 3-Loom preparation used to take place years back

Front room is very linear and is least used. The hen is breed and kept in this part of the house as shown in the fig) Currently, in this room, there are benches kept and are rarely used. There are certain buckets and pots where the water is stored.(as the region faces a shortage of water) This room currently is also a place where the washing machine is kept and the clothes are hung for drying.

9.3.1.7 Roon No.2 This room is the very same room where step 4 of saree making was happening 20 years back.

Today the wooden left over of the weaving machine is converted to sleeping cot.

This room number 2 is highly used space of the house.Most of the activities like watching TV,eating and relaxing happens here.

9.3.1.8 Room No.3 This room is the later addition to the existing plan.This room was previously used for cloth stitching activity .Today this room is used as a study/work room with a table kept.

9.3.1.9 Room 4 The room 4 is the kitchen,located on th southern side.Then years back there was fire chulha used for cooking and also gas stove. This is now replaced by LPG.2 years back there was extensive use of this chulha in the morning to cook samosas and and other stuffs .This was the occupation of the 9.3.1.10 Room 5 Washroom.This is located on the eastern side.

Figure 39

9.3.1.11 Relation ship between occupancy and space.

Sl N o

1

Space name

Occupancy

Type of activity

Location of activity with relation to the room

Start

End

Wall made of brick, cement plastered on both the sides.

Floor –Red oxide flooring WindowsFurnitures-

Loom preparation, Beedi making(then)

Loom prearatio n adjacent to external wall Beedi making adjacent to interior wall

Varies

Used interm ediatel y.and mostly during night

12’

Wall made of brick, cement plastered on both the sides.

Initially mud plaster on the interiors.

Floor –Red oxide flooring

Weaving (then) Today this is a multipurpose room used for sleeping,eati ng,and also as a family room

Used almost thoug hout the day and evend uring night to sleep

8’

Wall made of brick, cement plastered on both the sides.

Floor –Red oxide flooring

6’11 ”x 9’6”

12’

Wall made of brick, cement plastered on both the sides.

Tailoring(the n) Work area(now) Most used room by a person during this covid (work from home).

Cooking

Towards the south wall a cot is placed for sleeping, Towards the interior wall tv and cupboard.

Towards a interior wall

Towards eastern wall

4:00a m 6:00p m

6’8” x9’6”

8’

(Numberin g With relation to the plan)

Room1

< most of the time

Room 2

Max-5(then) Now 3

3

Room 3

1

4

Room 4

1/2

Wash room/

Floor to ceilin g heigh t(Aver age height of slopin g roof)

2

5

Description of space(wall,floor, Ceiling-material,texture and colours)

Area

1

18’9 ”x7’1 ”= 132.

8sqft

16’ x 9’ 6” =152 ’

8’

Wall made of brick, cement plastered on

(Especially during night)

8:00am 7:00p m

Chulha

both the sides.

Figure 41

Figure 40

4:006:00

10 Sun path diagram(analysising direct beam radiation)

Figure 42 sun path movement

The sun is mostly overhead,with its rays falling on the roof for the majority of the time.

Southern side of the roof is most important.

Understanding the sun path movement during various months and during the day. To understand the same lets observe the incident angle during various month , and the net radiation falling on different time of the day and year.

10.1 Observation for various months at 12pm.

1. October 22st 12PmIt is observed that the altitude made is 65.90.Therefore angle made by the sun ray to that of the normal =90-65.90=24.1.Since the roof is tilted by 250, θ=24.1+25=49.1.cos 49.1=0.65 Hence 65 percent of the radiation heats the roof. Note that cos24.1 would have led to 91 % radiation to fall on roof. This is considerably reduced because of sloping roof,as can be seen in the fig.

Figure 43

It is observed that the altitude made is 65.90.Therefore angle made by the sun ray to that of the normal =90-65.90=24.1.Since the roof is tilted by 250, θ=24.1+25=49.1.cos 49.1=0.65 Hence 65 percent of the radiation heats the roof. Note that cos24.1 would have led to 91 % radiation to fall on roof. This is considerably reduced because of sloping roof,as can be seen in the fig.

Figure 44

2. December 22nd 12Pm-

Figure 45

It is observed that the altitude made is 53.07.Therefore angle made by the sun ray to that of the normal =9053.07=36.93.Since the roof is tilted by 250, θ=36.93+25=61.93. cos 61.93=47.

Hence 47 percent of the radiation heats the roof. Note that cos36.93 would have led to 79 % radiation to fall on roof. This is considerably reduced because of sloping roof,as can be seen in the fig.

Figure 46 December 22st

Figure 47

3. March 21st , 12Pm.

Figure 48

It is observed that the altitude made is 75.42.Therefore angle made by the sun ray to that of the normal =90-75.42=14.58.Since the roof is tilted by 250, θ=14.58+25=39.58 . cos25.42=0.90 Therefore cos 39.58=0.77. as can be seen in the figure 15.

Therefore 77 percent of the radiation falling is heating the southern roof. Note that cos14.58 would have led to 90perc radiation to fall on roof. This is considerable reduced because of sloping roof

Figure 50

Figure 49

4. May 21st,12 pm

Figure 51

Sun has moved towards the northern sde of roof. It is observed that the altitude made is 81.80.Therefore angle made by the sun ray to that of the normal =9081.80=8.2 .cos8.2=0.98.Therefore 98 percent of the radiation falling is heating the southern roof.

Figure 53 Figure 52

5.

July 21st

Figure 54

In the first week of july sun begins moving backtowards south to complete the 8 shape by December.Sun has moved almost to the northern side of the roof .

It is observed that the altitude made is 80.12.Therefore angle made by the sun ray to that of the normal =90-80.12 =9.88.since the roof is tilted by 250, θ =9.88+25=34.8.cos34.8=0.82.Therefore 82 percent of the radiation falling is heating the southern roof.

Note that cos9.88 would have led to98perc of radiation to fall on roof.

Figure 56

Figure 55

From all the sun path diagram.It is clear that the roof receives more than 80% of the radiation falling on it at the peak time of 12 pm throughout the year. It is observed from the sunpath diagram sun being closer to the earth in the months of December to February, hence the value of θ is more hence the intensity of light is less.also, it can be observed that the sun moves faster during this month.In converse it can be seen that during the months of April may June the sun is farther away, hence the angle formed with the normal is lowest hence the intensity of radiation is more.

The sloped roof helps in increasing the value of θ, hence decreasing the intensity of the sun rays(greater the value of θ, lesser cosθ value. Further, it is also observed that the roof in the southern side is at a higher altitude as compared to that of the northern side, which is a positive aspect of the design as this part of the roof is exposed to higher radiation, This design feature shall reduce the radiation received by the occupants in the southern side.

10.2 Analysis of the sun path movement during a day

Figure 58 6:20am.

Figure 57 7 35am

April being the hottest month,having considerable longer duration of day light(12.29hours). we take this month to analyze the sun path diagram during day.

It is observed that that the angle formed with the normal to the east wall is 7.60 at 6am.cos(7.6)=0.991,therefore 99%percent of the radiation hits the wall in the morning. The height

of the wall being 7â&#x20AC;&#x2122; ensures that this ray of light falls on the east wall between 6am in the morning to around 8am.after which the ray falls on the northern roof. Angle formed with the normal at 7 45am is 25.56.Cos25.56=0.90,hence receiving the 90 percentage of radiation falling on it. There is no window on this side.In the morning between 6 am to 7 30 am the movement of the sun is fast ,hence the sun remains in the eastern side radiating the rays to wall only till 8am.there is 20 degree movement of the sun in 1 and half hours.

Figure 59 4:35pm

Figure 60 6pm

similarly ,It is observed that the sun reaches the western wall by about 4: 30 and sets by 6:30.The change of angle is 20 degrees in 2 hours.

Time 6: 20am 7:20 am 8:20am 9:20am 10:20 am 11:20 am

Angle 0.88 14.87 29.30 43.83 58.41 73

12:20 pm 1:20pm 2:20 pm 3:20 pm 4:20 pm 5:20 pm 6:20 pm

87.39 77.64 63.04 48.46 33.91 2.8 5.16

Inference-The above table clearly shows the rate of movement of sun during various time.11 to 12 rate of movement of the sun being very slow above the roof. Hence it becomes very important to design roof in this climate as it is exposed to direct sunlight between 9am to 4pm.

10.3 Observation and inference from other design elements with respect to sun path and activities ď&#x201A;ˇ

One of the important feature of this house is the provision of sylight in the roof.This skylight is on the southern side right above the working area. It is observed that this region where the 3 skylights are located receives suns direct radiation as the sun passes through this part of the roof in the months from November to December,as it is seen in the figure.

Figure 61

Considering the activities 30years back-As seen in the figure there are 3 skylights placed overhead of the high activity zone, where the mother of the house used to be involved in her occupation of weaving .This being an intense activity needs ample amount of light.

Ref- http://www.physicalgeography.net/fundamentals/7l.html https://www.pveducation.org/pvcdrom/properties-of-sunlight/calculation-of-solar-insolation

Figure 62

Refering to the above graphs it is observed that the the region where the skylight is located receives suns radiation at the rate of 1kw/m2(1000w/m2) (between 10:30 to 3:00pm,when the sun passes through the skylight in the months of november to december(from sun path diagram).

Also the area of the glass used is 0.15m x 0.20m =0.03m2.hence a glass of light receives intensity of 0.03 x 1000 =30w.hence the 3 glasses receives total intensity of 90w(direct radiation) andsky radiation of 30% of sky radiation(390w/m2),that is 11.7w/glass.As observed openings on the wall is minimum This room also has a window of size 60x85 facing south to allow for the light required to carry out the work.

Even today, though there is no handloom activities being carried out this room is primarily used for watching TV ,sleeping, eating or to simply sit and spend quality family time. ď&#x201A;ˇ

The entry to the house is towards the north. This room does not receive any direct form of radiation from the sun as the sun path diagram does not cross this room. This room has 2 openings of size 85x75cm.(wooden).So when the window is open it receives 30% of the solar radiation(sky radiation) (390W/m2), that is 248.625W for 0.6375m2 of a window. This room is very linear and was being used to spun the

threads into yarn on a spinning wheel called a charkha. Today this space being very linear is rarely used as a living room and the primary use remains to dry clothes and store extra water. ď&#x201A;ˇ

From the sun path diagram it is observed that the eastern side has no window. Hence The front room shall receive no morning sunrays. The location of the toilet to the south east side blocks all the eastern sun rays from entering the room.

11 Wind movement and humidity control.

As shown in the previous figures it is observed that the wind speed is high for the period of 5 months from june to September. The wind being prevalent from the western side. Since the area receives very high rainfall, and with the coastal coverage towards west the humidity in air is very high ,hence ensuring right flow of wind movement for dehumidification is very important.

It is observed that there is one window of size 60 x 85cm on to the western side.The wind entering this room does not circulate throughout the entire room as cross ventilation is poorly worked upon.

Figure 66 Figure 63

Figure 65 Figure 64

The ventilation and humidity control is the most important in this region if there is no proper filtering of the air the atmosphere reaches its dew point very soon,further with increased air pressure(when the fan is switched on) the relative humidity reaches 100percent very soon during

rainy season causing the condensation of the water droplets on the floor surface as can be seen on the above figure.

As the temperature increases relative humidity decreases.(as seen from the graph).Since the region is near the coast and from the humidity graph it is observed that the humidity in this region is mostly above 60% throughout the year ,the dew temperature too is relatively high.Which means the air reaches its dew point very soon.Hence the common phenomena of condensation causing the water droplets to settle on the floor is predominant.

Inference â&#x20AC;&#x201C;From the layout of the plan it is evident that cross ventilation is not effective as there is no rooms with oppositely placed windows to make way for the flow of wind.The flooring being red oxide acts as an absorbant,preventing the moisture from reaching the top.

In the fig 36, the picture of the room no.3(reference from the plan) shows the provision of table fan.The room beig very small,volume of the room being as low as 4.5 m3,needs to have proper disposal of hot air to ensure comfortable working atmosphere.

11.1 Humidity,wind and its relation to the temperature.

Humidity

Figure 67 April

I

Figure 68

I

11.2 Inference In this case it is important that the buiding design holds good in ensuring that there is correct crossventilation which is an important criteria to ensure dehumidification.The high moisture content in the atmosphere shall make the inhabitant feel more hot during the day.

i

12 Thermal mass and its relation to the materials used.

Figure 69 East wall properties

Figure 70 north wall properties

Figure 72 South wall properties

Figure 71 west wall properties

InferenceIt is observed that the outer surface temperature on all 4 sides of the wall is same,since the cross section is same on all 4 sides.Through the ground reflectance does not remain the same on all 4 sides it has got not much influence in the external temperature on all 4 sides of wall.

12.1 Understanding thermal mass of the walls and its contribution for the internal heat gain.

A

B

Thermal mass =m x s x Î&#x201D;T M=density x Volume Density of brick block=1800kg/m3.

Therefore M=1800 x 0.3 x 1 x 1 =540K J, Thermal mass=540 x 840 =453600J=453.6KJ the highest diurnal difference being in the month of jan and February =140C. Calculation for wall A Total heat transferred to the wall throughout the day from the outside=Thermal mass x diurnal range/10x60x60(thermal lagin sec)x2(half of the heat is tranfered inside and half outside) =453.6x 1000(in J) x 14/2x10x60 x 60 =88.2 W

Hence the wall that is exposed is acting as a 88.2W heater during the night and 88.2W absorber during the day.

Total heat absorbed by wall A=thermal mass(for 0.3m3)x (Total area of wall) =88.2 x (2.4 x 5 -0.516(Area of the window)) =88.2 x 11.484=1019.77 W. Similarly Total heat absorbed by the wall B = thermal mass x area of wall 88.2 x 7.2(3x 2.4)=635.04 W. Since south side receives maximum radiation,wall of higher thermal mass shall be effective in keeping interior cooler to an extent.and since the major activities happen in this room it is important to give proper shadding to ensure lesser radiation reaching this wall.

The external

12.2 Calculating thermal mass of the roof

Figure 73

Mass=Density x Volume =1900 x 0.02 x1 x 1=38kg

Thermal mass = 38 x 837=31806KJ=31.8.

Hence the radiation reaching interior=31.8 x 1000 x 14/2 x 6 x 60 x 60 =10.3 j/s.

Hence the capacity of the roof to hold the suns radiation is very less ,as compared to the wall.Therefore the steeper pitch of this roof increases the distance from the ground level, thereby decreasing the radiation reaching the surfaces in the interior

Figure 74 south roof

January the surface receives more direct radiation than april???(why is this graph and pv lighthouse giving different value)South facing pitched roof receives the maximum heat radiation of 969Wh/sq.m.

12.3 Heat flux calculation for west wall Q= A x U x Î&#x201D;T Transmitance,U=1/Ra Ra=1/f i +Rb+1/f o ,fi= surface conductance of the interior wall and f0= Surface conductance of the exterior wall.,Rb=Resistance of the core brick wall.

Resistance of the brick wall Rb1=0.30/1.210 = 0.2479,Resistance of plasters Rb2=(0.025/0.57 )x 2=0.0877 1/f o=1/13.18=Ro=0.002/0.026=0.076 (f0 Value from appendix 5.2) 1/f i= 1/8.12=Ri=0.005/0.026=0.192 Ro=0.192+0.2479 +0.076+0.087= 0.6029 sqm deg C/W

Therefore U=1/Ra=1/0.6029 = 1.6586 W/ sqm.deg C Î&#x201D;T =Ts-Ti

Ts, Sol Air temperature = To+I x a/k Since april is the hottest month ,For the month of april 19 at 1pm, Angle of the radiation formed with the normal on this day=90-83.44(altitude)=6.56 Cos 6.56=0.99.Therefore the roof receives 99% of the radiation.That is Net radiation=0.99 x I=0.99 x 982=975.57.(I=982 from PV light house website)(In this case we need to calculate the U value for the roof since Suns direct radiation falls on the roof) however in the evening it reaches the west wall at 5pm. The altitude is 21.85, Cos(90-21.85) =cos 68.15=0.37 .That is 37% of the direct radiation is falling on the west wall,net I=I x 0.37=664 x 0.37=247.12.

A(area of the west wall)=18m2,a(absorbance of white paint)=0.2, K=Conductance of air=0.026

Figure 76 April 19th 12pm

Figure 75 April 19th at 7pm

Ts=To +( I x a)/k Conductance of air=0.026/0.005(thickness of air film) =32+ (247.12 x 0.4)/5.2 =32+19 =51 Q= A x U x Î&#x201D;T, Î&#x201D;T= Ts-Ti =18 x 1.6586 x (51-25) =776.22 W This value shall be even more higher for the roof on april 19th at 1pm ,as the radiation falls on the roof during this time.

12.4 Inference Texture place a very important role in increasing or decreasing the surface conductance.Surface conductance in the southern side can be decreased by increasing the rough texture on the wall by use of naturalmaterials ,instead of creating a smooth surface by painting it white.

Further,Paint having the least absorbance towards the suns radiation shall reduce the capacity of the wall to hold heat. Keeping the external surface with high absorbing capacity is important in a region of high diurnal difference of temperature.

13 Sun light hours Sketch up plugin-sun hours has been used to understand the total sunlights hours falling

Architecture features as can be observed from the above figure, the only shading that turns effecting in preventing th suns radiation from heating is the large overhangs of roof .There is is no overhang projections over the windows.

13.1 Total surface radiation of wall

Figure 78 South wall total radiation

Figure 77 West wall total radiation

It is observed that the south radiation is least in the months of may,june, july and highest in January,December and February.(since th sun is closer to the south wall in the months of jan December and February,radiation is high in these months).The highest radiation being 780Wh/sqm and the lowest being 78Wh/sqm at around 12pm.

Similarly west wall receives the least radiation in the months between june to august .The lowest radiation being 212 and highest being 438, at around 14pm.

Figure 79 north wall

Figure 80 East wall

It is observed that the October to febraury the total radiation received is 0, whereas the total radiation received varies from as low as 19Wh/sqm in the month of march to 329Wh/sqm in the month of may.

Also it is observed that the east wall receives the highest radiation at 10am.This radiation ranges from as low as 177Wh/sqm in july to 479Wh/sqm in February.

14 Psychometric chart

It is observed that without any design strategies the comfort level achieved achieved is just 1% as can be seen in the designated blue region in the above graph.It is observed that to achieve desired 100% thermal comfort the above mentioned design strategies needs to be achieved.

However there can be certain regions of thermal delight that can be achieved through design strategies which is the most critical part of architecture.The regions of extremes as observed the the house studied above includes.

ď&#x201A;ˇ

A region in the backyard when the traditional technique of use of Chula is seen.

ď&#x201A;ˇ

Cooling and dehumidification has 77.8% role in bringing about thermal comfort.

ď&#x201A;ˇ

Sunshading of windows have 29.5% contributionin achieving thermal comfort.

14.1 Design for overhangs for this climate.

14.1.1 Design of overhangs between December to june.

Figure 81

As observed in the above graph it is observed that the 90 percent of the hours falls above the comfort zone in the months between December to june.It is observed that horizontal overhangs in the south ofangle 50 degree would be efficient in blocking the sun rays throught the year.Similarly vertical shading of angle 300 from the south would be sufficient to block the radiation from the east and angle of 550 would be sufficient in the western side to block the radiation.

14.1.2 Design of overhangs between june to December.

From the figure it is observed that Been june to December the design criterias remain same as that the design criterias between December to june.

Figure 83

15 Design strategies

Figure 82

Figure 85

Figure 84

Figure 87

Figure 86

Figure 89

Figure 88

Figure 90

Figure 91

16 Design strategies to be worked on 

Reworking on the placement of windows and opening to ensure proper cross ventilation.There was heavy use of chulha once upon a time, however there was no design of openings to facilitate the movement of hot air.Provision of openings to let the hot air to exscape and drawing in more cooler air can be an option to think upon.



Southern side room is excessively used.Hence a high thermal mass wall shall facilitate in storing heat and keeping interiors cool.



In room number 2 there were 2 windows previously for ventilation .However during the extension of house northern window turned useless .This room used to get filled with smoke when chulha was in use hence addition of openings in the western side and also outlet in the higher level shall control the atmospheric condition inside.This is important to control temperature and also humidity in the interiors.



Large overhangs can be added to ensure protection against rain and direct radiation.



Reworking on the norther room to convert it from the storage area to usable seating area can be done.



However the use of magalore tiles , and the floor to roof hight usage of red oxide flooring,smaller opening are the plus point in the design.