INVESTIGATING THE ENVIRONMENTAL PERFORMANCE OF BAMBOO ARCHITECTURE IN THE WARM AND HUMID CLIMATE OF BALI, INDONESIA

Olivier Dambron

April 2016

AA SED MSc Sustainable & Environmental Design 2015-16

Term 2 - Research paper 2

Architectural Association School of Architecture Graduate School

AUTHORSHIP DECLARATION FORM

Research paper 2

TITLE: INVESTIGATING THE ENVIRONMENTAL PERFORMANCE OF BAMBOO ARCHITECTURE IN THE WARM AND HUMID CLIMATE OF BALI, INDONESIA

NUMBER OF WORDS: 4768 STUDENT NAME: Olivier Dambron

DECLARATION: “I certify that the contents of this document are entirely my own work and that any quotation or paraphrase from the published or unpublished work of others is duly acknowledged. “

SIGNATURE:

DATE: 25th of April 2016

TABLE OF CONTENTS

Abstract …………………………………………………….….. 06

1. Introduction …………………………………………..…….. 06

2. Context ……………………………………………………… 07

2.1 The warm and humid climate of Indonesia ….. 07

2.2 The local climate of Ubud in Bali ….…….….… 07

3. Bamboo, a viable resource for Bali ………..…….……… 08

3.1 Overview on bamboo ……………..…………… 08

3.2 Bamboo a locally abundant natural resource.. 08

3.3 Sustainable bamboo design principles…….… 09

4. Case study: the Green School ………………..………… 10 4.1 Overview of the Heart Of School ..…………… 10

4.2 Environmental analysis of the site…….……… 12

4.3 Thermal performance of the Heart Of School.. 13

4.4 Daylight analysis .………….…………………… 15

5. Conclusion ………………….……………………………… 15

References …………………….……………………………… 16

Annexe …..…………………….……………………………… 17

INVESTIGATING THE ENVIRONMENTAL PERFORMANCE OF BAMBOO ARCHITECTURE IN THE WARM AND HUMID CLIMATE OF BALI, INDONESIA

OLIVIER DAMBRON Sustainable & Environmental Design MsC, Architectural Association, London, UK

April 2016

Abstract

The purpose of this research is to analyse the thermal performance of an exclusively bamboo based construction using natural rods through a case study of a contemporary bamboo school near the town of Ubud on the island of Bali in Indonesia. The historical relevant data of the town is explained as well as the general physical and climatological conditions appropriate to the use of the material. Basic guidelines for bamboo selection, preservation and processing will also be reported, for them being a critical aspect to allow the phenomena they create. The different aspects of the specific school of the case study were also analysed covering the construction specifications, architectonical layout and their interaction and performance in the environment. Its thermal performance was evaluated through fieldwork using data loggers and spot measurement tools along with data gathered through interviews with the users. Conclusions were made establishing connections between the physical specification and fieldwork. The qualitative and quantitative results concerning the ability of bamboo architecture to provide comfort with low energy consumption, will be regarded with respect to passive design strategies for warm and humid zones.

Key words: bamboo, vegetal rod, warm and humid climate, abundant resource, thermal performance

1. INTRODUCTION

The fast and uncontrolled development of emerging countries around the tropical belt, is leading to the spread of improvised architecture. Northern customs of living from more developed countries situated at high latitudes are being replicated around the equator, where climatic conditions are opposite. These new inappropriate living spaces constitute a significant threat to the environment, as means to reach comfort rely exclusively on mechanical elements. Sourcing of ecological local materials along with the development of suitable environmental designs are key for these countries to sustain their new ways of living. The island of Bali is severely exposed to massive tourism all throughout the year. For the past decades “ruthless” developers have focused on the southern part of the island, building fully air-conditioned high rise resorts, encouraging foreigners to maintain their customs from abroad. Not only has this phenomenon gentrified the local balinese population away, but also constitutes a real threat by gradually separating locals from their culture. One of the direct consequences is the decrease of tolerance from the Indonesians regarding their environmental comfort conditions. However, further inland, lies the balinese cultural capital town of Ubud where genuine traditions are perpetuated and relation to nature kept strong.

Abundant around the tropics, bamboo has traditionally been used as a construction material for the warm and humid climate. Although varied uses and applications in building construction have established bamboo as an environment-friendly, energy efficient and cost effective option,

recent transformation techniques of the material have derived it from its natural state. Therefore, drawing attention of designers away from its initial potential as a vegetal rod. Reporting guidelines for bamboo selection, preservation and processing in Indonesia will be necessary to set the conditions in which bamboo holds its best potential to generate sustainable architecture.

A significant challenge that has slowed the development of bamboo architecture resides in its acceptance by the society. Bamboo remains widely misunderstood and attributed exclusively to extreme contexts, either for old traditional uses (vernacular architecture, scaffolding, etc) or temporary emergency sheltering. However, several noticeable examples of bamboo buildings have attempted to elevate the material to more contemporary and modern uses, at locations where the strongest bamboo species grow.

The focus of this paper will be on Indonesia, as it detains a strong handcrafting heritage combined with a traditional know how regarding the use of bamboo. This set of conditions creates new possibil i t ies to generate sustainable and environmental architecture using natural bamboo rods to which modern lifestyles can relate.

2. CONTEXT

2.1 The warm and humid climate of Indonesia

Indonesia lies between latitudes of 11°S and 6°N. The almost uniformly warm waters that make up 81 % of Indonesia's area (figure 1), ensure that diurnal temperature difference remain small, resulting in a warm and humid climate. Split by the equator, the archipelago is entirely tropical in climate, with daily air temperatures ranging from 22 to 33°C and relative humidity between 60 to 95% with the majority of the population living in naturally ventilated houses. Winds are moderate and generally predictable, usually blowing in from the south-east during the dry season (June to September), and from the northwest during the rainy season (December to March) as a result of Indonesia's geographical locat ion as an archipelago between two large continents. The resultant monsoon is augmented by humid breezes from the Indian Ocean, producing significant amounts of rain throughout many parts of the archipelago.

Local wind patterns, however, can greatly modify these general wind patterns. For its location on the equator, the archipelago experiences relatively little change in the length of daylight hours from one season to the next; the difference between the longest day and the shortest day of the year is only forty-eight minutes.

2.2 The local climate of Ubud in Bali

Ubud is centrally located on the island of Bali at an altitude of nearly 220 meters above sea level, with the nearest coast at more than 10 km (figure 2). Annual temperatures (figure 3) are slightly cooler than in the coastal areas, ranging from about 20 to 30°C with narrow diurnal temperature range of +/- 7°C which requires permanent need for ventilation to relieve from any source of heat. Rainfall is important with an substantial annual average of 2244mm and relative humidity levels above 80% which explains often overcast sky conditions and dense vegetation. For these same reasons, glare is strong as diffuse radiation from the sky is predominant over reflected radiation of the ground (Koch-Nielsen, H. 2002). Ubud's wet season runs from November to March with intermittent daily rain. During this period the surrounding vegetation is luxuriant. The dry season takes place from May to September with very few rainy days, low humidity levels and brighter skies.

Although these conditions were systematic until recently, Indonesians reckon witnessing climate change as these conditions have now become unpredictable. Until the early 2000, an annual sudden change of wind direction occurred during a week in April and another in September, these events were traditionally the object of social gatherings in the rice fields and a celebration for the annual kite festival. Although wind directions and time at which they occur are now scattered, prevailing winds can still be considered to be south-eastern and north-western, respectively during the dry and wet season.

Fig. 2. Map of Bali (source: Google)

Fig. 3. Climate analysis of Bali (source: Meteonorm)

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Fig. 1. Map of Indonesia (source: Google)

3. BAMBOO A VIABLE RESOURCE IN BALI

3.1 Overview on bamboo

The use of modern building materials has brought the market to undermine the craft of building with bamboo. It is highly probable that using bamboo in architecture will become more popular again in the years to come for a number of reasons. On the one hand, these are due to the rapid rate at which it grows and the large quantities in which it is available, thus making it easy to obtain. On the other hand, the favourable material properties such as low weight, tensile strength of steel, compression resistance of concrete, ease of processing and, last but not least, the increasing need for housing for the growing population of the world. This is further supplemented by the fact that the regions in which bamboo grows are nearly identical to those regions with the highest population growth rates.

3.2 Bamboo a locally abundant natural resource

Asia is home for 67% of the worldwide bamboo distribution. More than 1000 species can be found within the latitudes ranging from 50° North to 20° South. Bamboo is a fast growing grass that requires careful harvesting for the best intended performance. Culms reach full length in 8 months time, with maximal diameter showing as it comes out of ground. Two years are necessary for the first skin to fall off and for branches to appear. The best appropriate time to harvest a bamboo culm is after 3 years as it reaches its optimal and stable internal density, which can only be verified with sonic tests. Once harvested, as culms will be put out to dry under the sun for two weeks, they are subjected to shrink. Successful results are determined by low rates of shrinkage to prevent bamboo from cracking. The culms are then plunged into a hot boron based mixture for 24 hours. This treatment necessary for internal pores to lose their sweetness, therefore preventing insects from eating the internal cells. Finally, green poles are put out in the sun once again until they dry and become yellow as the chlorophyl disappears (Stamm, J. 2008).

In order to achieve expectations, fast growth, high quality, high yield and strength, it is necessary to source species with the best adaptability to conditions of local climate, soil and topography. Traditional knowledge further confirmed by more recent studies, suggest for best practice to use 3 particular species for construction purposes in Indonesia. Figure 4 depicts ones that are abundantly growing in Indonesia and locally referred to as :

1- Petung (Dendrocalamus Asper):Height of culm: 18-25 m Diameters: 10-20 cm Thickness: < 2 cm Timber bamboo used for structural elements and furniture.

2- Tal i (Gigantochloa Apus):Height of culm: 10-20 m Diameters: 10 cm Thickness: < 2 cm D e n s e a n d s t r a i g h t bamboo used for roof structures, furniture and scaffolding.

3- Duri (Bambusa blumeana):Height of culm: 10-15 m Diameters: 6-12 cm Thickness: < 2 cm Curvy and bamboo used for flooring, railings and furniture.

Fig. 4. Species used for construction and found abundantly in Indonesia

3.4 Durable bamboo design principles

Bamboo is a well recognised sustainable resource for the construction industry in tropical zones. However, as it is not possible to certify culms to grow one identical to another, building with bamboo is subjected to the quality of workmanship. The unpredictability of bamboo anatomy makes it difficult to develop mechanical solutions to assemble construction elements. This can be coped with in countries such as Indonesia, as their is a popular culture holding a substantial handcrafting heritage, allowing designers to rely on efficient and customised solutions.

Several basic principles for building with bamboo are to be followed to ensure maximum lifespan of construction elements:

Particular attention has to be addressed to joinery which are key points in construction, especially as it is to bamboo, the unprotected and vulnerable part subjected to cracks if not handled carefully. A widely adopted technique resides in shaping the extremities of the hosting pole as a “fish mouth” in order to hold the adjacent one and to transfer loads efficiently (Hidalgo, L, O. 2003). Traditionally pinned with bamboo sticks and tied with rope, these joints are now threaded and bolted. Additional cement can be casted inside to increase strength for key structural elements.

As a porous organic material, bamboo can either absorb or lose moisture. Any excessive variations in direct contact with bamboo will affect the durability of the material’s performance (Kramer, K. 1985), therefore solutions to prevent it from rain and direct high incidence solar radiation are obligatory, especially on the windward sides of the building as water splashes will reach deeper.These requirements can be coped with in different ways. One would be to ensure that the roof’s overhang extends out enough, so that the tip maintains a 45° angle with the ground with respect to the base of the bamboo structural element. If the angle could not be reached otherwise, lifting the base of the culms up by casting a concrete base or allocating a stone will also reduce the exposure with respect to the roof.

In Bali, thatched roofs are called “alang alang”. It is a very old roofing method commonly used in Indonesia. Apart from being widely available and low cost, it presents similar advantages to grass roofs which naturally are weather-resistant. Since there should not be a significant increase to roof weight due to water retention, a roof pitch of at least 40 degrees is required to allow for precipitation to travel quickly down slope so that it runs off the roof before it can penetrate the structure. Thatch is also a natural insulator, and air pockets within straw thatch insulate a building in warm weather, helping in keeping the building cool during hotter periods.

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Fig. 5. Picture of fish mouth joint with bamboo pin (source: courtesy of Pt. Bamboo Pure)

Fig. 6. Diagram of roof angle for water and sun protection

4. THE GREEN SCHOOL

Located near Ubud on the island of Bali, The Green School is a recent built example (2007) of bamboo tropical architecture by Pt. Bamboo Pure. The school is attended by nearly 500 students, both foreign and local, from kindergarten to high school. The resulting educational context is quite marginal in the sense that an international community of children are learning as they are directly exposed to a natural environment.

4.1 Overview of the Heart Of School

The site is centred on the main building called the Heart Of the School (HOS), which is surrounded by a multitude of smaller satellite buildings. The HOS will be the focus of this investigation. For ease of description, three parts of the building can be identified as A, the northern spiral, B the central and C the southern.

Fig. 8. Aerial view of site along the eastern Ayung river (after: courtesy of Pt. Bamboo Pure)

The masterplan features a well spaced layout to promote openness in order to maximise wind circulation. The sloped topography towards the east also decreases chances for buildings to mutually obstruct wind one to another.

Fig. 9. Western elevation of part A

The structural principle of the building resides on the hyperbolic shaped cores at the centre of each part of the HOS, which supports the weight of the thatched roof (Stamm, J. 2006). All other elements are made from the three bamboo species previously reported in this paper. Floorings, ceilings, stairs, railings, furniture and adaptable blinds are made from derived handcrafted products of the bamboo culm. The overall features a lightweight structure.

The roofs are pitched according to the requirement for water evacuation and overhangs extend out long enough to protect the base of the most eccentric culms. In case it is not sufficient, adaptive opportunities such as the bamboo blinds depicted by figure 11, can cope with rain, sun and glare protection.

The building is confined only by its roof as there are no walls, allowing the building to be opened up to more than 80 % of its elevation. With floors and partition made extremely permeable to maximise air movement (figure 12), and also considering acoustic limitations of the material, the program is distributed to prioritise privacy of classrooms and avoid disturbance by adjacent users. As a result the classrooms can study efficiently but the overall occupancy of the floor area remains unoptimised.

Fig. 10. Western elevation of part B

Fig. 11. Eastern elevation of part C

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GRAPHIC ARTS CLASSROOM[20 people]

BREAK/LUNCH AREA[100 people]

COOKING CLASSROOM[10 people]

LIBRARY[10 people]

CLASSROOM 1[30 people]

OFFICES[20 people]

WORKSPACE[8 people]

CLASSROOM 2[30 people]

IT ROOM[10 people]

STUDY AREA[15 people]

STUDY AREA[20 people]

STAFF ROOM[15 people]

BREAK/SITTING AREA[50 people]

C B A

Fig. 12. View of offices from second floor

Fig. 13. Floor plans with program distribution and occupancy

A commonly used solution is to allocate rubber from old tire as dampers to cope with the squeak of bamboo ensembles being walked over by users.

The school runs from 8:30 am to 3:30 pm, Monday to Friday with a 15 minutes snack break at 10 am and an hour lunch break at noon which are the only times where important activity is allowed on the ground floor. Classrooms and offices are used all throughout the day with study areas slightly busier during the afternoon.

With the warm and humid climate at hand, the vegetation grows rapidly and densely, therefore conditions of the landscape that were considered during the design stages must have been significantly different from the actual ones. Figure 16 depicts this time related difference by showing an aerial picture taken in 2012 and one in 2016.

Bushes, mid-height vegetation and high palm trees surround part B and C of the HOS, obstructing severely breezes from any direction at height of openings, depriving the habitants from comfort during the hot hours of the day. This is further supported by two interviewed teachers who reckon lacking air movement in those areas, whereas a third one working on the ground floor of part A reported to often feel cool breezes crossing.

4.2 Environmental analysis of the site

The HOS is oriented, in length, North East to South West, with the long facades perpendicular to the axis of prevailing North-West and South-East winds. The site presents a strong potential for the HOS to benefit from natural ventilation, as its orientation was prioritised to wind exposure against minimising solar exposure (East-West). As the building can be considered to be an almost entirely semi-outdoor space due to its amount of openings, cross ventilation is very effective regardless of the wind directions. Moreover, the building is located on top of a hill overlooking a river to the East. The South Eastern wind will cool down as it approaches the streaming water and its path will subject it to accelerate along the rising topography (figure 14). Supposedly, the air movement should gain speed as it reaches the top of the hill and therefore deliver effective cool breeze to the users of the building (Koenigsberger, O. 1973). To the north western side lies a sports field covered with grass, of which the unobstructed length allows the North West wind to recover speed. Moreover, during the hot period, the evaporative cooling effect of the grass affects the air temperature driven by the wind towards the school.

Although the potential for the site to benefit from natural ventilation is strong, the actual context reported through the conducted fieldwork shows differently as depicted in figure 15. The recovery of wind speed is verified with recorded values increasing towards the building, but as the grass is less overshadowed and therefore dryer at the centre of the field, its reaction to solar radiation will be closer to the one of bare ground, thus absorbing and radiating more for less evaporation. The increase of air temperature will direct the air masses upwards, away from the building’s openings.

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Site section view, North West - South East: Potential for natural ventilation with the prevailing winds

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Gymnasium Football field (75x34m) Heart Of School Primary classrooms Ayung river

Fig. 14. Site section view, North West to South East axis: Potential for natural ventilations

Fig. 15. Site section view, North West to South East axis: Current conditions for natural ventilations Wind speed (Ws, Dry Bulb Temperature (DBT), Mean Radiant Temperature (MRT).

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Gymnasium Football field (75x34m) Heart Of School Primary classrooms Ayung river

Site section view, North West - South East: Current conditions of natural ventilation with the prevailing winds Wind speed (Ws). Dry Bulb Temperature (DBT). Mean Radiant Temperature (MRT).

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S-E windWs : 0.0 m/s

DBT : 30.9 °CMRT : 33.9 °C

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Ws : 0.2 m/sDBT : 32.1 °CMRT : 39.3 °C

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Ws : 0.7 m/sDBT : 31.9 °CMRT : 34.3 °C

Grass

2008 2016

Fig. 16. Comparison of surrounding vegetation

4.3 Thermal performance of the HOS

In order to assess the thermal performance of the building, preliminary spot measurements were conducted all throughout the HOS to identify relevant thermal activity.

Wind speed measurements confirm the assumed obstruction caused by the surrounding vegetation over the ground floor and first floor of part C (figure 17). Although air movement increases with heights of floors, the long windward roof spans may divert breezes away from the users if openings are not planned adequately.

There is a noticeable slight increase towards the part A as the area is less obstructed by vegetation. The overall wind speeds measured throughout the building indicate a relatively more stagnant air on the first floor of all three parts of the HOS compared to the ground and second floor. This is caused by the roof overhangs reaching out at height of the first floor, to protect users from glare as well as structural elements from sun and rain for the price of obstructing the wanted direct ventilation.

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The design of the roof is not suited to generate significant wind driven effects as it has permanent openings on both windward and leeward side regardless of the wind direction. Moreover, the small outlet areas do not generate differences of pressure to exhaust air from the entirely opened facades. The cooling of the building relies essentially on the effective 360° cross ventilation.

With wind speed being a categorical parameter for cooling in the warm and humid climate, the spotted temperatures follow a symmetrical behaviour throughout the building. As wind speed lowers, temperature increases and vice versa (figure 18).

Three data loggers were allocated in the part B as it is central and also the most densely occupied, one on each floor and a fourth one outdoors.

Fig. 17. East elevation with wind speed measurements (after: elevation by Ibuku)

Fig. 18. East elevation with air temperature measurements (after: elevation by Ibuku)

directed towards the internal spaces, which can be coped with the existing retractable blinds. This is the case in part C (figure 22), as an important proportion of the roof is assembled to the second floor which hosts the staff room.

TEMPERATURE [°C]SOLAR RADIATION [W/m2]wind speed [0.01 * m/s]

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Recordings were made during a school week in April 2016 from Monday to Friday (figure 20). However, attention will be drawn to the three last days which display a variety of different climatic conditions:

13/04 Wednesday featured precipitation in between 11:30 am and 1 pm. 14/04 Thursday featured a partly cloudy sky obstructing intermittently the sun during the hottest period of the day. 15/04 Friday featured a clear sky with sun with a more regular amount of radiation.

The logs indicate clearly the lightweight structure of the building, as semi-internal temperatures behave with no time-lag with respect to the outdoor variations.

During daytime, there is a 1° difference in between the ground and the first floor and another 0.5° in between the first and second floor. This gradual increase of temperature is proof of an existing stack and buoyancy effect. The rise of warm air can take place easily as most of the vertical elements have important permeability. Moreover, the structural hyperbolical core acts as a corridor for warm air to reach higher openings. As a result warm air stratifies in the upper levels, causing discomfort to users if wind speed is too low.

Although temperatures are mainly within the comfort band, during the hot hours of the day, intense solar radiation heats up the surrounding grounds and roof’s surfaces causing the the first and second floor to overheat. Even though thatched roofs do not hold much heat, some of it is picked up by winds on the windward side and

Fig. 21. Structural core allowing warm air to circulate through floors

Fig. 20. Chart of data logged in the HOS (see annexe)

Fig. 22. East elevation of part C with partial roof assembled to the second floor

5. CONCLUSION

Bamboo at its most natural state offers sustainable possibilities to generate contemporary environmental architecture that is affordable, functional and also reconnects users with nature.

The exclusively bamboo built Green School of Bali presents a successful thermal performance as the internal temperatures remain permanently below the outdoor temperature during the hottest hours of the day. Further wind driven refurbishments of the roof and specific tailoring of the surrounding vegetation will enhance internal air movement to increase comfort of the users. Efficient use of adaptive opportunities are to be explained thoroughly to the users to allow more satisfactory control over their environment.

The conditions required for the material to be one of the key alternative to tropical architecture can easily be met in countries where it has always been growing, as the cultures and know hows have evolved accordingly in the past.

By heating the soil, solar radiation induces significant air movement, in consequence influences wind speed. The latter peaks right after noon and drops down around 6 pm to remain low during the night, leaving for the hot air trapped under the roof to only slowly cool down. However throughout the night, the ground floor and the outdoor temperature show a gradual difference of 1 to 2°C, which lasts until the morning. This clearly indicates the role of the thermal storage capacity of the ground, releasing heat through conduction and convection as the outdoor temperature drops. The substantial impact over the building’s temperatures can be understood by the very large surface of the roof exposed to the ground as it carries extended overhangs, therefore funnelling indoors the dissipated heat (Szokolay, S. 2003).

4.4 Daylight analysis

Yellow bamboo has a light reflectance of nearly 50%. The apparent details of construction on every element of the building adds a roughness to the interior surfaces which diffuses daylight. The main feature allowing daylight to enter the building is the circular top opening above the structural cores of each spiral. Its diameter, ranging from 2 to 3 meters, allow abundant sunlight into the interior spaces. Considering the very high sun path at this very low latitude and the high humidity levels, glare can be intolerable. For its very high position which is rarely in sight of the users, the top opening does not cause significant glare issues. However, direct sunlight on bamboo elements is to be avoided for durability, for these reasons, a white translucent canvas was allocated to cover the top opening in order to diffuse daylight. Also, the supporting core structure received special treatment of a more reflective coating preventing the poles from cracking.

Spots measurements were taken during a sunny day and reveal that most areas receive the required 300lux for educational building (figure 23). The far extending overhangs used for the HOS help limit view of the sky from the users. Moreover it diffuses the strong reflections from the ground. Since most of the daylight is indirect, deep plan areas remain subjected to use artificial lighting systems even in bright sunny days (figure 24).

Fig. 24. Part C of the HOS under a bright sky.

Fig. 23. Section view of part B of the Hos: daylight analysis (values in lux)

REFERENCES

[1] Koch-Nielsen, H. (2002). Stay Cool. A design guide for the built environment in hot climates. James & James Ltd.

[2] Hidalgo, L, O. (2003). Bamboo - The Gift of the gods. Bogotá. ISBN 958 – 33 – 4298

[3] Kramer, K. (1985). Bamboo as a building material. Institute for Light weight structures. Nr.31, 1985. Stuttgart.

[4] Koenigsberger, O. Ingersoll, T. Mayhew, A. Szokolay, S. (1973). Manual of Tropical Housing and Building, Part 1: Climatic Design. Longman Group Ltd., London.

[5] Stamm, J. (2006). Manual for bamboo selection, classification, preservation and processing. Popayán (2008), Colombia.

[6] Stamm, J. (2008). Following the natural advantage of the giant Grass. Popayán (2008), Colombia .

[7] Szokolay, S. (2003). The role of Thermal Mass in Warm-Humid Climate Housing. pp55-61, PLEA 2003, Santiago.

CONSULTED LITERATURE

Chaudhari, P. (2012). Solar control for schools in warm and humid climates: impacts on visual and thermal comfort. Architectural Association SED MSc (2012). London.

Smith Mathis, M. (2008). Social housing in Costa Rica’s warm and humid climate. Architectural Association SED MSc (2008). London.

Givoni, B. (1994). Passive and Low Energy Cooling of Buildings. Van Nostrand Reinhold.

TEMPERATU

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07:00

08:00

09:00

10:00

11:00

12:00

13:00

14:00

15:00

16:00

TEMPERATURE [°C]

Radiation [W/m

2]

Wind speed [0.01*m

/s]

Outdoor Tem

perature

Ground floor Tem

perature

First floor Temperature

Second floor Temperature

Values

Date

Dissertation project

Towards open source bamboo architecture with the vegetal rod

Handbook for environmental bamboo architecture in the tropics

Bamboo limitations

Current developments (coating, controlled growth…)

Combination with other materials