THE THERMAL COMFORT OF THE JAVANESE TRADITIONAL HOUSE IN A HIGH DENSITY ENVIRONMENT
A Case Study at a Javanese Traditional House at Kemlayan Kampong, Surakarta
Paper ID: P – 03 – 27 – L
Abstract
In the past, The Javanese Traditional Houses was a good representative of hot humid tropical houses that can well-adapt to the local climate and well collaborated with a local belief and tradition as well as local material. At present when the population is growing up, people need many houses or new spaces, and they can use a new environment to build in any way. But sometimes, because of the limitation of income, many of them still use a piece of the existing land in around the house especially in environment of the traditional houses in certain ways as it happens at kampong kemlayan, Surakarta, Central Java. So, it can be predicted that such a phenomenon will impact to the environmental density and quality of outdoor and indoor climate. Because of air movement problem both indoor and outdoor, the heat gain on building will increase externally and internally. It influences to the thermal comfort mainly in the building. The question is how Javanese Traditional House can contribute in providing the thermal comfort in a dense environment.
The used research method was by studying the data collected in the field by using HOBO Data Logger on two different characteristics of buildings. One building represented a completed Javanese Traditional house. Meanwhile the other building represented a tightly closed one. Then they were compared to the ARCHIPAK program as analyzing software.
The research result was that obviously the original Javanese Traditional House still has a better ability in providing the thermal comfort especially at a dense environment the other one. It is proved on the condition of indoor air temperature that can be categorized in comfort zone.
Keywords: Thermal Comfort, Javanese Traditional House, Dense Environment
1. Introduction
House is a primary need for people that should be owned by every family. By owning a self house, people can do all activities save and comfortable. In the past when population was not as many as at present condition, people could have a wide house with adequate land area. At that time, the building density and population was still very low, and natural air circulation was still easy to access. The building, well-known as the traditional house, becomes a comfortable house with a large yard having many types of vegetation. Now when the population is growing up, and supported by the change of people in mind set, social-cultural, education, and economy, so certainly the need of housing is experiencing a change as well. Therefore, it makes the house price to be more and more expensive.
In other hand, not all people have an ability to have a proper house to live. Because of the tradition on the housing renting system in the past and at present or because of limited financial ability, they use and develop space by space in the same building. Even the other phenomenon is by developing new houses at the existing land in around the building from generation to generation. It makes the housing settlement become denser and in other side it affects thermal condition in side the building.
Such phenomena are common in the system of the Javanese Traditional housing both in Surakarta and Yogyakarta. They called it Magersari System (Winarna, 2005). It happens at Kampong kemlayan as well. In the growth of this Kampong, there are many kinds of new houses emerging in around of the Javanese Traditional Houses there. Besides that, there are many changes of building function of the traditional houses and even in building itself significantly
2. Climate of Surakarta
Surakarta is one of big cities in Indonesia especially in Central Java. Surakarta, well known as cultural city, lies in 7.9oSA.Surakarta’s climate is a hot humid tropical region with temperature varies from 20.7 oC to 33.5oC. The air humidity is around 60-92 % with the level of precipitation as all parts of Indonesia is extremely high, around 38 mm to 338 mm.
Table 1. Surakarta’s Climate
3. Condition of Kampong kemlayan briefly
The history of the existence of Kampong Kemlayan, according to Aliyah in 2000, was very close related to the history of Surakarta Kingdom in the past, since Pakubuwono II until Pakubuwono XIII as the King of Surakarta Kingdom.
Kemlayan is a traditional settlement specifically for Kingdom’s artists, such as: dancing creator and traditional music artist. According to Aliyah, 2000, in the past there were a grouping of settlement based on ethnic, such as: Javanese, Chinese, Arabic, and European settlement. Besides that it can be based on social statues, profession and local condition. That can be identified on the name of the kampong, like Kemlayan its self taken from the word of Mloyo (Kraton’s pengrawit).
Kemlayan is one of the traditional kampongs in Surakarta having a uniqueness. It lies in city center of Surakarta and it has many houses with Javanese Traditional characteristics with narrow pathway as circulation space and building border. Up to 2000, Kampong Kemlayan consisted of 32 buildings having Javanese Traditional characteristics that still exist with different building quality. Meanwhile the emerging of new buildings at Kampong Kemlayan is also high. This phenomenon will affect to the density of the settlement.
Commonly, at present most of traditional buildings at Kemlayan still use wooden material and thick brick material for wall and column, traditional tile for roof material, and grey tile or ceramic for floor material. Spatial configuration on the Javanese Traditional Houses at Kampong Kemlayan is mostly still completed (Aliyah, 2000) consisted of Pendhopo, Gandok, pringgitan and so on.
Figure 1: Javanese Traditional House and Kemlayan Environment (source:author)
Figure 2: A narrow pathway and one of people’s activity (source:author)
4. The Theoretical Base of Building Density and thermal
The theoretical studies of building density related to the thermal aspect state that in high density environment there is a correlation between density factors and building heating. Santamouris, 1997 said that the implication of high density environment both building and population will affect to the building heating, air circulation and environmental shading. He added that high density is a main factor influencing the change of microclimate and determining to the condition of environmental ventilation and air temperature.
In other hand, the high density environments give the benefit in reducing solar direct exposure through shading to the land and building surface. This strategy is commonly used in hot dry tropical region. The influence of building density in a environment also depends on wind direction, the arrangement of building spaces and building height (Santamouris, 1997: 100-1)
5. Javanese Traditional House works in climate
Based on the research results of Javanese Traditional House in responding climate in which one of them was research result of Santosa conducting a research about Traditional House and Settlement related to the socio-cultural and physical phenomena and spatial formation (PLEA, 1999:334)
Santosa stated that the intelligent of the traditional building’s response to the inclement climate was through the physical built-up or form of architecture itself. The Indonesia multicultural interaction has not produced a single architectural style, while a common cultural base can be identified, strong regional, cultural and architectural form, and characteristics persist.
According Santosa in other part stated that the characteristics of the traditional house in responding climate are done through the use of lightweight material, large opening, open-plan design, building orientation, and building lay-out.
6. Methodology
In this research, data were collected through direct measurement by using Hobo data logger on two different characteristics of building. It was placed 3 sensor devices on each building: those are at Pendhopo, indoor space and outdoor space. The measurement was conducted for 3-4 days of measurement in the end of January. Besides that, it was used Thermo-hygrograph to measure the air humidity.
Meanwhile for air velocity was assumed at zero point. It was considered that there was no significant air velocity in that environment influencing the thermal comfort. Beside above data, it was also used data from BMG to be analyzed by simulation method with ARCHIPAK Program to predict the thermal comfort of each building or room annually.
From the two methods, the result will be compared to have a conclusion of the thermal performance of Javanese traditional houses in high density environment.
7. The Result of Measurement by using Hobo Data Logger
7.1 Measurement on building 1
Figure 3: The Result of Measurement by using Hobo Data Logger on Building 1
From the result of measurement by using Hobo Data Logger conducted for three-four days (figure 3), it can be noted that thermally on the first building representing a completed traditional building; indoor air temperature condition (bed room) at 10 am- 6 pm is always lower than outdoor. Meanwhile at 6 pm- 11.30 am, indoor air temperature is always higher than outdoor. This means that building elements at traditional building can respond outdoor climate in which during taking the data the outdoor temperature tended to be low.
Meanwhile at Pendopo with open plan design, the air temperature condition looks a like with outdoor air temperature condition. The air temperature condition is less high than outdoor condition at 6 pm to 11 am and less low than outdoor at 11am to 6 pm. Therefore the indoor condition of the traditional house 1 is comfortable to live.
7.2. Measurement on Building 2
Figure 4: The Result of Measurement by using Hobo Data Logger on Building 2
From the figure above it can be seen that indoor air temperature shown by the data of working room and pendhopo is relatively higher than outdoor air temperature. When outdoor air temperature condition is in low level, 22 oC to 25 oC, indoor air temperature condition is in rather high level in 25 oC to 27 oC. Therefore, the temperature difference between indoor is around 3 oK higher than outdoor air temperature.
In other side when outdoor air temperature starts to go up, the indoor air temperature also increases as high as the outdoor condition. Therefore, if the outdoor air temperature will achieve more than 31 oC (on dry season), so the thermal comfort at indoor space is difficult to fulfill especially between 11 am to 6 pm.
Comparing the data of two buildings above taken by using Hobo Data Logger, it can be ensured that the completed Javanese Traditional House still has an ability to provide a thermal comfort than the tightly closed Javanese Traditional House in a dense environment.
8. Simulation Result by ARCHIPAK Program
By inserting some indicator of analyzing with ARCHIPAK program, it can be known that relatively indoor air temperature in January until December on the two Javanese traditional houses studied is around 26 oC to 28.3 oC. It means that the buildings have an ability to reduce the influence of outdoor air temperature and humidity. Clearly, it can be seen on Table2 and Table 3
Table 2: The Hourly Indoor air temperature of building 1
Table 3: The Hourly Indoor air temperature of building 2
Profile 1: Indoor Air Temperatur on building 1
Profile 2: Indoor Air Temperature on Building 2
9. Conclusions
Based on the two methods used in the research on the two kinds of Javanese Traditional House at Kampong Kemlayan, those are by direct measurement on the building and by simulating using ARCHIPAK Program, it can be concluded that in a dense environment:
1. The completed Javanese traditional house still has a better ability in providing thermal comfort than the other one.
2. On the situation in which outdoor air temperature is extremely low, the completed Javanese traditional house (building 1) can provide higher indoor air temperature. So can the other one (building 2)
3. Vice versa, when outdoor air temperature is extremely high, the indoor air temperature of building 1 tends to be lower. This phenomenon is followed by the building 2. In the same situation the indoor air temperature tends to be the same as the outdoor air temperature.
4. The tightness of building will affect the building heating especially in high density environment.
5. By keeping the originality of the Javanese traditional building, it can contribute to provide the natural thermal comfort for people although the building lies in a high density environment.
Acknowledgements
The author wishes to acknowledge to Laboratory of Building Science, Institute of Technology Sepuluh November Surabaya and Laboratory of Building Science, Department of Architecture, Sebelas Maret University Surakarta providing all facilities in the research. In this opportunity as well, the author wishes to thank so much to Ir. Wibowo & family, and Bapak Margono & big family who provided their houses to be measured.
References
Aliyah Istijabatul, 2000, Landasan Konsep Konservasi Kampung Kemlayan sebagai Kawasan Seni dan Budaya Jawa di Surakarta, UNDIP-THESIS, Semarang
Santamouris and Asimakopoulos,1997, Passive Cooling of Buildings, James and James,London
Santosa, Mas, 1999, Proceeding of Passive Low Energy Architecture, PLEA International, Brisbane
Winarna, 2005, Abstract International Settlements and Affordable Housing, ITS, Surabaya