LESSONS FROM A BEDOUIN: DESERT ADAPTIVE ARCHITECTURE Rawan Suheil Qobrosi Paula Cadima
Architectural Association School of Architecture Architectural Association School of Architecture
rawan.qubrosi@gmail.com paula.cadima@aaschool.ac.uk
Fig 1: The Bedu of Wadi Rum, a culture on the brink of extinction [1]
WHICH ARE YOUR ARCHITECTURAL (R)SOLUTIONS TO THE SOCIAL, ENVIRONMENTAL AND ECONOMIC CHALLENGES OF TODAY? Research summary This research paper examines and highlights the unique characteristics of the Bedouin tent used to withstand the harsh climate of the Wadi Rum desert. It compares the environmental performance of an original Bedouin tent with a contemporary urban tent found today within the boundaries of Wadi Rum village. The findings helped identify the nomadic qualities and strategies that can always be implemented as new environmental architectural features to improve current modern homes and most importantly preserve a rich dying culture. Keywords: Bedouin, black tent, Wadi Rum, desert, Jordan.
1. Introduction Bedouins of Wadi Rum have undergone tremendous changes in lifestyle; shifting from living in Bedouin tents to settling in permanent homes in Rum village in a short period of time. This was due to several factors since Wadi Rum was classified by UNESCO as a world heritage site in the 1970s [2]. This has led to different private and public companies managing the area which restricted the development in the protected area and imposed rules on the special Bedouin inhabitants [3]. Located in Jordan, Wadi Rum is part of Jordan’s desert region. Wadi Rum protected area (WRPA) is located to the south of Jordan between latitude 29°34′35.4″ North and longitude 35°25′11.74″ East. Within the WRPA, Rum village is the only settlement that is affected by the various regulations and government constraints. This village is purely made up of Bedouin inhabitants. After living a pure nomadic lifestyle, Bedouins began to settle in permanent homes in Rum Village, partly due to the restrictions on living in the WRPA, and also encouraged by Jordan’s government – having constructed a school and a clinic in Rum village (Fig 2). This led to more Bedouins settling in permanent homes. As a result their lifestyle shifted from pastoral livelihood to modern tourism and services. In the last few years, Rum village witnessed an alarming growth where more than 300 houses were built (Fig 3). The government later built high walls surrounding the village houses [6]. This transition had a negative impact on the Bedouins and their nomadic lifestyle, as they now live in houses which rely on mechanical systems, and have lost the ability to live a sustainable adaptive lifestyle. Holding onto their heritage, many Bedouins have setup a
contemporary version of the tent within the boundaries of their houses [6]. This paper discusses the unique adaptable environmental characteristics of the Bedouin tent of a pure nomad in the desert of Wadi Rum, and compares it with a contemporary tent within the boundaries of Rum village houses, based on first-hand fieldwork [6].
Fig 2: Perspective view of Rum village in 1980’s [4]
Fig 3: Perspective view of Rum village in 2012 [5]
2. Wadi Rum Climate Wadi Rum has intense solar radiation almost all year long. Its warm period is between June to the beginning of September, where the average temperatures exceed 35°C (Fig 4). The cold period starts in the end of November and lasts until the end of February, where temperatures drop to 2°C and chances of snow are common, but the average temperatures can reach up to 20°C. Finally, the mild period is
between March and May, and late September to early November, and is the time when the Bedouins couple with the outdoors.
Wadi Rum has a desert climate with large daily swings between day and night, that can reach 12-14K. This diurnal temperature swing provides comfortable cool outdoors in the hot months of the year compared to the hot internal spaces, making migration of the Bedouin a standard pattern during the cool nights [6]. RH 100%
40
2
(°C)/(kWh/m )/(m/s)
35
33.6°C
30
26.5°C 24.1°C
25
15
14.3°C
12.6°C 11.3°C
10 5
50%
20.7°C
20
2.0°C
0%
Fig 4: Monthly Mean, Minimum, Maximum dry bulb temperatures for Wadi Rum with ASHRAE 55 adaptive comfort band in green [7]
3. Bedouin Architecture The black tent was found in Mesopotamia around 3000-400BC. This tent moved from this birth place to reach the Atlantic coast of Mauritania in the west, and the high mountains of Tibet in the east. “Without this tent the people of the middle east might never have ventured into the desert.” [8] Its geographical distribution was due to the domestication of goat, sheep and most importantly camels that could travel longer distances and carry greater loads in the harsh desert, which ultimately helped change and increase the size of the tent [8]. This continuous geographical span of the black tent makes it hardly considered a primitive
form of dwelling, but rather an evolutionary structure [9]. It is a timeless architectural dwelling that adapted to fit this wide range of environments and is used to this day. 3.1 Shading The main role of a Bedouin tent is to act as a shading device. The dark brown color of the goat hair actually provides extra shade, which is a distinctive advantage of such an opaque fabric to block the sunlight compared to light colored fabrics [9]. 3.2 Materiality The Bedouins weave their roofs, walls, floors and even their furniture. Almost all black tents use goat hair [8]. This is the only natural material that has the strength, length, and
special tensile qualities which give the black tent its unique form [8]. The goat hair is considered a responsive material in the cold period, because when it rains the fibers become swollen and shrink as they absorb water in, and the weaves tighten [8]. In addition, a special quality of goat hair is its natural oiliness, which acts as a water repellent. Despite these qualities, it still does not provide the best environment in the cold period. This is why Bedouins have an open fire within one of the tent’s sections, where it can remain closed and the smoke can sweep through the weaves [10]. In the warm period the weaves become loose and extend, which helps the heat to scatter. The black color of the tent is expected to absorb the heat and create uncomfortable internal conditions. However, because the weaves become loose during the warm period, a stratification effect is created around the surface of the roof [11]. This is why the radiant heat is never felt while sitting under the tent. In addition, the Bedouins raise the roof away from them in the hot period, which further reduces the effect of the heat. While in the cold period the Bedouins lower their roofs to act as a heat source from the heat absorbed [11]. 3.3 Tent Shape and Structure The Bedouin black tent is built from goat hair strips that are hand woven by women on ground looms, called cloth breadths. Each strip is 60-80cm wide (Fig 5). These strips can be woven as long as the tent [10]. Afterwards, the cloth breadths are sewn edge to edge to create a large rectangular roof [10]. Also, as a support system, tension bands are sewn across the strips.
Fig 5: View of goat hair strips on the roof cloth with detailed sewn edge to edge
The edge of the tension bands are attached to a stay fastener and the hemp rope stay (Fig 6), creating an independent system.
Fig 6: Stay Fastener and Hemp rope stay
The walls are called “Ru’ag”, and are a totally separate element from the roof. They are attached to the structure using large pins. The Ru’ag is usually made with patterns using wool hair [8]. The roof of the tent is supported by wooden poles, which give the tent its shape and structure. Also, the wooden poles remain separate from the tent fabric, which allows for added flexibility. 3.4 Flexibility for Wind Control A key feature of Bedouin architecture is the flexibility and separation between the structure (the wooden poles), walls, and roof which allows the tent to move with the wind. This fascinating system is capable of absorbing the shocks of strong winds, where the structure moves with the winds [8], and the roof can be lowered by the Bedouin for less
resistance. According to the season, Bedouins can place their tents behind a mountain to minimize the strong winds [11]. In the warm period the tent can be left completely open, where the roof can act as a shading device and the walls are rolled up for cross ventilation. These walls can be moved to either side according to the desired winds. During the cold period the tent is situated according to the sun position for passive solar gains, and the black roof can be lowered for the radiant heat. Moreover, the tent can be totally closed from both sides and extra walls are built to act as a buffer and wind breakers [11]. 4. Case study in Wadi Rum Village: Environmental Performance of a Traditional and a Contemporary Tent This research is based on first-hand fieldwork in Wadi Rum of Jordan [6]. The research was conducted in April and July of 2013. An original Bedouin tent of a semi-nomad Bedouin woman “Um Omar” in the desert of Wadi Rum was compared with a contemporary urban tent within the boundaries of the house of a settled Bedouin family “Um Mufleh Al Zalabia” in Rum village. Spot measurements were undertaken to measure air and surface temperatures, as well as the wind velocity and illuminance levels below and outside the tents. Interviews with Bedouin inhabitants were carried out to learn about the users’ habits and lifestyle, and observations helped identifying the main characteristics and differences between the two types of tents. The location of the tents in relation to Rum village is shown in Figure 7. The fieldwork studies revealed that in the village there are some families that are fully settled and others that still remain semi-
nomads. Bedouins enjoy the open air and prefer the outdoors whenever its more comfortable; they do not like concrete homes. Um Omar moves to the desert during the spring period for the grazing of her sheep and goats, and spends the rest of the year in the village. On the other hand, Um Mufleh is a fully settled family that has a contemporary Bedouin tent within its house boundaries, which stays there all year round. During the cool summer nights they sleep outdoors and cook bread outside in the evening. In winter they use the tent during the day as it provides a warm comfortable space. 4.1 Main Differences between a Traditional and a Contemporary Urban Bedouin Tent Um Omar’s traditional tent is made out of goat hair, and has all the features and characteristics of Bedouin architecture highlighted in section 3. It is a three pole tent (Fig 8 and 9) 15-16m long by 3.5-4m wide. It has two sections: a men’s quarter to the east and a women’s quarter to the west. The front opening is always oriented towards the south. The roof is supported by the three rows of wooden poles; the middle row is usually higher than the front and back with a minimum of 15cm [11]. Those middle poles act as the main structural element, where wooden planks are woven within the tension bands (see Fig 11) to help prevent the tearing of the goat hair, and provide a full separation from the structure.
Rum Village (Um Mufleh’s Tent)
Um Omar’s Tent
Fig 10: Um Mufleh’s Contemporary urban tent
Fig 7: Wadi Rum Preserved Area Map [12]
Fig 8: Um Omar’s Tent
Fig 9: Plan of Um Omar’s tent
On the other hand, the Contemporary tent of Um Mufleh does not follow the foundations of Bedouin architecture. Although the contemporary tent is made out of goat hair, the structure of the tent was totally transformed to have a steel frame structure, and a pitched roof (Fig 10). In addition, the tent is fixed within the concrete block boundaries of the house.
4.2 Effect of Shading During the fieldwork the ground surface temperature below Um Omar’s traditional tent was measured. Recordings showed almost 18K difference between shaded sand and sand exposed to the open sky. It was apparent that the opaque color of the Bedouin tent helped reduce the glare. Nevertheless, solar rays could pass through the weaves and provide a comfortable visual environment. Illuminance level was recorded at 500 lux while the external was registered as high as 97000 lux. The shading effect of the contemporary tent was similar but with 10K difference between shaded and exposed sand. 4.3 Impact of Materiality According to measurements during the fieldwork, Um Omar’s tent surface temperatures had a difference of 10K between the shaded areas of the roof and the exposed ones, revealing large variations below the tent. However, the air temperature below the tent was identical to the outdoors, measured at 31°C (Fig 11). In the Contemporary tent, the inside surface temperature of the goat hair roof was measured at 73°C and 65°C at the shaded part of the roof. Also, the back boundary was measured at 51°C. Although the goat hair has distinctive qualities for shading, the air
temperature below the Contemporary tent was lower than the outdoors by 3°C.
and hinder the Contemporary tent’s ability to adapt and take advantage of benefits from air movement.
Ta=31°C
Fig 11: Air temperature and internal surface temperatures of goat hair at Um Omar’s tent
4.4 Flexibility to wind The strong south west winds were blowing through the men’s section of Um Omar’s tent (Fig 12). The wind speed reached 5.3m/s in front of the tent, while inside it was measured up to 1.8m/s and 1.5m/s at the back. This air movement gave a cooling sensation and promoted heat losses from the body by convection.
Fig 12: Front view of the Men section with blowing wind
Although the ambient temperature measured in the contemporary tent was lower than the outdoor temperature, there was no air movement (Fig 13), creating a stuffy space that the family never used except in the cold period. The Contemporary tent is usually placed in a limited available outdoor space within the house boundaries. These boundaries are also affected by the location of the house within the village, as they are raised for more privacy from the streets and neighbors. However, they block the wind flow
Fig 13: Spot measurement of Um Mufleh house and contemporary tent
The aerodynamic shape of the traditional tent is more adaptable to the outdoor conditions. This system is very primitive yet complex with high efficiency and adaptability to move with the desert winds [10]. The tent is flexible and the roof is adaptable to cope with the strong winds compared to a fixed pitched roof of the contemporary tent. Hence, the Contemporary tent fails to handle the outdoor conditions, because the tent cloth is attached to the steel; when the air circulates at higher speeds it keeps being blown off since the structure never moves with the desert winds. 5. Conclusions The study shows how the original Bedouin tent is an integrated whole system that can be easily adapted to deal with the harsh outdoor desert climate and provide a better living environment for its users. The dynamic shape – detached structure from the walls and roof – gives the original Bedouin tent elasticity to cope with strong winds and deal with the different wind directions. In addition, the
movable walls and roof also provide adaptable opportunities for its inhabitants, allowing them to control the shading and maximize or minimize the solar gains through the surfaces. The transitional spaces created by such a modular system can help adjust the internal temperatures especially during the cold period. As for the materiality, the use of the local martial and its responsive qualities contribute to providing a comfortable microclimate within the enclosure. In contrast, the current contemporary village tents, which became an image of the past architecture, are built today with nonresponsive material, rigid structure, fixed orientation, and non-adaptable openings. Thus, it does not preserve or inherit any of the unique passive strategies found in their vernacular architecture that could be adopted and implemented within the current modern house. The fieldwork demonstrates that the original tent (Um Omar’s tent) performed better than the contemporary urban fixed tent (Um Mufleh’s tent), in particular in dealing with strong winds and in providing flexibility to take advantage of the air flow during the hot period. Although the contemporary urban tent provided lower air temperature below than the outdoor temperature, unlike the traditional tent, its inflexible system did not to take advantage of the air movement and led to a stuffy environment underneath it. This resulted in a non-responsive Contemporary tent that is only used during the day in the cold period. 6. References [1] Abou Zeid, M. (2010). Bedouin Heritage Project, The Bedu of WadiRum, a culture on the brink of extinction [online] Available at:
http://socialdocumentary.net/exhibit/Mark_Abouz eid/1830 [Accessed 1 May 2015]. [2] UNESCO, (2011). Wadi Rum Protected Area. [online] Available at: http://whc.unesco.org/en/list/1377 [Accessed 1 May 2015]. [3] Brand, L.A. (2001). Development in Wadi Rum? State Bureaucracy, External Funders, and Civil Society. International Journal of Middle East Studies, Vol. 33 (4), pp.571-590. [4] Domenech, B. (1986). Perspective view of Rum village in 1980’s. [online] Available at: <http://www.jordanjubilee.com/meetfolk/bedouin .htm> [5] Chossclimber (2012). Perspective view of Rum Village in 2012. [online] Available at: <http://chossclimbers.com/testing/jordan/jordanpart-1/> [6] Qobrosi, R. (2013) Keeping the Nomad : Adaptive Bedouin House in Wadi Rum, MSc Dissertation, SED Sustainable Environmental Design, Architectural Association School of Architecture, London. [7] Brager,S., de Dear (2001). Climate, Comfort & Natural Ventilation: A new adaptive comfort standard for ASHRAE Standard 55. Center for Environmental Design Research, Univ. of California. [8] Faegre, T (1979). Tents Architecture of the Nomads. John Murray, London. [9] Drew, P (1979). Tensile Architecture. Granada Publishing Limited. [10] Abed Al Rahman (2013). Characteristics of the original Bedouin tent [interview] (Private Conversation on the 1st April 2013) [11] Abu Adel (2013). Lifestyle of a Wadi Rum Bedouin living in the village [interview] (Private Conversation on the 1st April 2013) [12] Wadi Rum, (2005). About Wadi Rum [Online] Available at: <http://wadirum.jo/About_Wadi_Rum_htm>