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Fishy Joinery

The Fish Mouth is named after the way one bamboo piece “bites” into its counterpart. This traditional joinery technique makes use of the bamboo’s intrinsic properties by evenly distributing loads across the full section of the bamboo culm.
The art of making this joint can be broken down into the following steps:

1. Gather the right materials:

  • Four pieces of treated dry bamboo, three have a larger diameter than the last one. For instance, with a Petung piece of 10 cm diameter, try to have a smaller piece of around 6 cm.
  • An electric drill, with bits of 3 to 4 mm diameter
  • A mutik (traditional bamboo carving knife), chosen according to your dominant hand (a)
  • A curved chisel (b)
  • A hammer (c)
  • A few wooden dowels (at least 10)
  • A pencil (d)
  • A ruler/tape measurer (e)
  • A hand saw (f)
  • Protective wear
Photo: The traditional tools needed to make a fish mouth. (©Bamboo U).


2. Prepare the fish mouth:

i. To add strength to the joint, the top of the mouth on the column should be cut close to a node (use the diameter as reference).
Then, divide into four equal parts.
Between the node and the end of the column, draw a line around the surface. The distance from the end of the column and the line should be the same as the radius of the beam.

ii. With your pencil, draw an approximate shape for your fish mouth.
Hold the column and saw along the diagonals.

iii. Then, carve out the mouth’s shape in upwards motions (working in the same direction as the bamboo fibres)
3. Make the hole joint:

i. Take the third, smaller piece of bamboo. It will act as the tie between the column and beam.

ii. Draw out its diameter on the beam, where the fish mouth will sit. Taking the chisel and the mutik, carve out the “hole”.
Slot the piece in, it should fit in tight and all the way through to the opposite culm wall.
Then, drill and dowel.

iii. Slip the column over the smaller bamboo piece to secure the fish mouth to the beam. Drill and dowel through the column and the small bamboo at opposite angles.

In this form, the joint is commonly used for furniture design and smaller structures.

4. Make the cross-brace:

If used in construction, the joint should be strengthened by adding a cross-brace between the beam and column at 45° angles with both the column and the beam.

i. To achieve this, measure the same distance from the fish mouth to where the cross-brace will sit on both the column and beam.

ii. Measure the values of a and b (see drawing). They determine the depth of your cut. Saw accordingly.
iii. Using the mutik, carve out the right shape for the brace to sit on the beam or column.

iv. Secure it by drilling in dowels.

The art of joining bamboo together relies principally on a strong understanding of the material as well as a careful hand (or two). The fish mouth joint testifies to beautiful craftsmanship and strength. It is something we are privileged to be able to share here and during our courses.

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Special Species

It may be hard to believe, but there are 1,400 documented species of bamboo on the planet! They are spread around the world, though about 900 (64%) of them naturally grow in Southeast Asia, including 145 specifically endemic to Indonesia.

With just one species, you can produce a variety of products, anything from food to construction material. This post is about 7 of the most important species we use for construction here in Bali.

Dendrocalamus Asper | Bambu Petung

This is the biggest bamboo we use. Strong and dependable, it is used in most of our bamboo buildings. You can see structural and traditional use of Petung at our Bamboo Office.

Average heights: 15 -30 metres

Average diameters: 8 to 20 cm

Principle use: construction and food (the young shoots are considered delicious!)

Distinguishing features: the aerial roots- little hairs, just above the nodes.

The use of Bambu Petung at our Bamboo U Office

The combination of Bambu Petung and Bambu Tali  at our Bamboo U Office

The use of Bambu Petung at Sharma Springs House at Green Village in Bali, Indonesia


Dendrocalamus Asper Niger | Bambu Petung Hitam

Due to a genetic mutation, this is a naturally black tinted version of Bambu Petung. Though the poles exhibit less structural strength than their blonde counterparts, they are often used for their beauty. A great example of this species in use is: The Minang House at Bambu Indah.

The use of Bambu Petung Hitam at Minang House at Bambu Indah Hotel in Bali, Indonesia 


Gigantochloa Apus | Bambu Tali

Bambu Tali has a series of qualities which make it an interesting building material. One of them is its flexibility, it can be easily manipulated and is used for making bamboo ropes, a valuable element of the construction process. In fact, Tali in Bahasa Indonesian means ‘rope’.

Average heights: 8-22 metres

Average diameters: 4-13 cm

Principle use: handicraft, furniture and construction.

Distinguishing features: long fibres and very little tapering (in comparison to Petung).

The use of Bambu Tali in our tensile tent on the new Bamboo U Campus, as a structural element and as rope.


Gigantochloa Atroviolacea | Bambu Tali Hitam

This is the black tinted variant of Gigantochloa, very similar to Gigantachloa apus but slightly larger and extremely elegant.

The use of Bambu Tali and Bambu Tali Hitam in the Moon House at the Bambu Indah Hotel in Bali, Indonesia


Bambusa Blumeana | Bambu Duri

This species is commonly known as Thorny Bamboo, as its shape is less straight and regular than others. In our designs, it not only serves us structurally but, it also becomes a beautiful aesthetic element.

Average heights: 20-30 metres

Average diameters: 10-18 cm

Principle use: construction and decoration.

Distinguishing features: its swollen nodes and unique shape.

The use of Bambu Duri bones in the Sharma Springs House at Green Village in Bali, Indonesia


Thyrsostachys Siamensis | Bambu Jakarta

Bambu Jakarta has a particularly yellow hue. This is an appealing characteristic which we use in our designs, particularly in our furnishings or smaller structures. You can see Bambu Jakarta being featured in one of our past yurts.

Average heights: 7 to 13 metres

Average diameters: 2 to 6 cm.

Principle use: food, paper and construction.

Distinguishing features: bambu jakarta has especially long internodes, ranging from 15 to 30 cm in length. The culm walls are also especially thick, giving this species its structural integrity.

“Fishing Rod Bamboo” of the Pseudosasa Genus | Bambu Pancing

Pancing in Bahasa Indonesia means ‘to fish’, consciously highlighting the elemental characteristic of this bamboo species. In construction and design, it is particularly used for furniture or decorative purposes, such as covering cables or tubes living spaces.

Average heights: up to 6 metres

Average diameters: 10-18 cm

Principle use: construction and decoration.

Distinguishing features: bambu pancing is recognisable because it tapers starkly towards the end, exactly like a fishing rod would.

The use of Bambu Pancing in furniture at Sharma Springs House at Green Village in Bali, Indonesia


Bamboo’s diversity is complex but understanding this is a vital element of how it can become the variety of objects which make up our day-to-day life. We express this range in the designs we create and innovate around; it constitutes a core element of our workshops and our bamboo universe. With each course, we pass on knowledge that is founded in fostering each bamboo’s various characteristics and promoting their individual strengths. We find that awareness of differences marks the first step to a sustainable future. Join us at Bamboo U to learn more about how to grow, design and build with bamboo.

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Swaying Bamboo

Experiencing an earthquake in a Bamboo house.

It’s 4 in the morning. The night is still dark and the wind softly whispers to the trees. I open my eyes and sit up in my bed. Everything around me seems to be spinning. Am I dizzy? or still dreaming maybe? As the seconds pass, the bamboos accelerate their waltz and looking out to the window, I can clearly see it’s triangular frame sway from side to side. The poles are singing now, grinding as would the mat of a ship sleeping in an agitated port. What is this curious terrestrial swell that rocks my crib? Slowly, the waves asleep, and so do I…

At the morning table, as I share my nocturnal experience, I am told that Lombok underwent an earthquake of 7.0 magnitude. The date is August 5th. The news report hundreds of demolished dwellings, taking a multitude of lives. The image of concrete walls cracking, failing and collapsing in horrific din contrast with my souvenir of bamboo poles under enchanting, subtil and momentary vertigo. In silence, I blame the myth of the 3 little pigs, which preached heavy materials to the World, while condemning grass huts… Could this change our minds?

Bamboo has both lightweight and elastic properties, making it an ideal material to resist earthquakes stresses. In 2012, a 7.6 magnitude seisme hit Costa Rica, and while nearly 200 concrete houses were damaged, at least 30 bamboo constructions survived effortlessly in the epicenter. Three years later a shock-wave of 8.1 magnitude set back Nepal of 800,000 buildings and 800 lives. The International Network of Bamboo And Rattan (INBAR) has since emitted an initiative to help the country recover from the crisis: in partnership with parties from the private sector, they are developing a number of modern bamboo building systems that meet international ISO standards and have excellent anti-seismic properties. “These systems and related technologies are now mature and offer an affordable, durable, highly renewable, and rapidly deployable source of building materials for affected communities”, says Dr. Hans Friederich, INBAR’s Director General.

Lombok’s traditional Sasak homes are composed of thatched bamboo walls, dirt floors, and woven reeds roofs. When feeling the first tremors, the inhabitants of these vernacular houses ran out, as everyone else. Not a single traditional dwelling was affected that day, even as the concrete houses around them crumbled. In a country where masonry architecture has become a synonym of progress more often than not, these structures are bringing an important new look onto ancient indigenous wisdom.


Credits: Jules de Laage, Program Manager at Bamboo U.

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New Bamboo U Campus Project

Design Build Bamboo

Build with us

Bamboo U is building a bamboo campus. We are building and designing the campus as an ongoing process with the help of students, architects, engineers, and designers from around the world. Bamboo U is a way to share the experience and knowledge that has been developed by Ibuku and green school over the past decade. The buildings on the bamboo U campus will showcase the best of what we have learned about bamboo construction as well as be a place to experiment with new ideas and structural concepts. Our intention is to combine the best of what we have learned, while experimenting with new ideas.

Design Build Bamboo

A Living Campus

We call it a living campus because we are asking the people who attend our 11 Day Build and Design Intensive to build and design the campus with us. We have developed a concept and a masterplan for the space, but the details for each building will evolve as we learn from ideas developed out of our educational programs. The campus will be composed of a classroom, a workshop, a bamboo harvesting forest, a dining area, a kitchen, and a bamboo sleeping lodge. There will also be a natural pool fed by a spring located onsite. The project is phased according to the editions of Bamboo U, and the first phase is the construction of our kitchen and dining area. Once this is complete, we will move the Bamboo U program from its current location at The Kul Kul Farm. Our programs are all inclusive. Participants can eat and sleep on site.

Keep reading to learn about the structures we are building.

The Kitchen

Bamboo U has already created a fantastic concept for its kItchen dining space. It was born out of a creative exchange between the Bamboo U team, Elora Hardy from Ibuku, and Neil Thomas from Atelier one. We’re very excited because this will be the very first concrete free structure ever created by us. We are partnering with Change Climate Bio-epoxies to sample their products and build a zero-cement permanent structure. Learn more about this structure soon, here in our blog.

The Workshop

This will be the largest structure on site. Spacious enough to have up to 40 people working on bamboo carpentry projects at any given time. Plus it will have space for important tools such as table saws, standing drills, jigs, CNC machines and 3D printers. It will be designed as a modular bamboo post and beam structure. A series of identical frames will be assembled by students on the ground and then raised into place. As the Bamboo U program grows, so will the length of this building – as different groups from the next editions of Bamboo U will put up more frames, elongating the structure. Our September Bamboo U participants will help with the creative design process and come up with the architectural design for this building.

The Classroom

Bamboo U is focused on hands-on participatory learning where we engage people on a kinesthetic and emotional level; there will be lots of learning by doing. However, we do value good old fashioned classroom time designed to teach the theory behind what we practice. This learning space will embody the organic shapes and curves that characterize Ibuku’s designs. But, unlike most of the classrooms out there, it will be and open air space that makes you ask: “Am I in a classroom, or outside in a forest that happens to somehow have a roof?” We will bring to life a beautiful encounter between the learning space and the surrounding area.
Linda’s Bamboo Forest
Many things have been learned since John Hardy first began construction of Green School’s all bamboo campus 10 years ago. Ibuku–our professional design and build partner–has been hard at work constructing over 50 unique structures since 2010. This led to major strides in developing the potential of bamboo construction here in Bali. The late Linda Garland inspired John Hardy to build with Bamboo. She showed him the power of this giant grass. Her son Arief has since gone on to develop sustainable bamboo harvesting methods which we teach during Bamboo U. If you don’t properly harvest bamboo it can be unsustainable just like any resource. In Linda’s honor we are creating a Bamboo forest as part of the campus to showcase a range of bamboo species, because this is where it all starts with an incredibly fast growing plant.

Please join us to build a future with beautiful, innovative, and awe inspiring sustainable structures.

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Arch Daily: Surprising Material Alert – The Black Bamboo

© José Tomás Franco

As a construction material, bamboo is resistant, versatile, grows rapidly and is immensely friendly with its own ecosystem and its agroforestry environment. In addition, it presents a large number of species that deliver different diameters and heights. But are there also variations in its color?

We are truly impressed with the work of architects, builders, and artisans who use ‘blond bamboo,’ which moves between yellow and brown tones. These species are abundant and easy to harvest, and therefore are more common and accessible. However, there are a number of species that have a darker coloration and could revolutionize bamboo architecture in the future. Here we present black bamboo.

Despite growing a little slower than the blond species, black bamboo presents an attractive range of dark tones that vary between dark coffee and black, depending on the species and its place of origin.

There are different theories that could explain the dark coloration of these species, but according to Arief Rabik, an expert in the management and production of bamboo forests and director of Indobamboo, could be due to a genetic mutation that would give an evolutionary advantage within forest systems, since black usually absorbs a greater amount of light.

© José Tomás Franco
© José Tomás Franco

However, Rabik warns us that we should not be seduced by the young black bamboo because although it presents an even darker and aesthetically cleaner coloration, it is still not ready to be used in construction and will crack easily. “Young bamboo is sugar cane, not bamboo,” he says.

© José Tomás Franco

Like its more traditional relatives, black bamboo grows mainly in tropical climates, but it can also be found in private collection gardens in South America and Australia, where even darker, jet-black species have been seen.

In some cases, as it is more difficult to find, its value can double that of the blond bamboo species, but there are parallel darkening or dyeing techniques that deliver incredible results through the burning and application of oils.

© José Tomás Franco
© José Tomás Franco

Featured Species

By mixing different species, black bamboo can be used in all parts of an architectural project; from the structure to landscaping, in addition to building its floors, walls, stairs and any other element.

Structural Species

Dendrocalamus Asper Nigra – Giant Black

The Giant Black or Asper Nigra species, with a typical diameter of 15 cm and a culm thickness (section walls) of 15 mm can be used in the primary structures of a building. The maximum usable length of the Giant Black species is about 18 meters, however, you can get the 20 meters usable with base diameters of more than 20 cm.

Gigantochloa Atroviolacea – Java Black

This species is very versatile and has a typical diameter ranging from 5 to 10 cm, and a length of between 8 and 10 meters.

© José Tomás Franco

Ornamental and/or Interior Species

Bambusa Lako – Timor Black

It is characterized by a typical diameter ranging from 3 to 6 cm, and a length that varies between 3 and 6 meters.

Phylustachys Aurea Nigra – Black Aurea

This species is used mostly in decorations and lightweight fencing, with a typical diameter between 1 and 3 cm (may be larger), and a length between 2 and 3 meters.

© José Tomás Franco

By Jose Tomas Franco

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Arch Daily: If We Were To Design The Ideal Building Material, It Would Look A Lot Like Bamboo

“Bamboo is close to an ideal structural material.” This statement by Neil Thomas during his talk at Bamboo U, which took place in November 2017 in Bali, really caught my attention. Neil is the founding director of atelier one, a London office of structural engineering, whose outstanding projects include stage and scenography for the Rolling Stones, Pink Floyd, and U2; art installations by Anish Kapoor and Marc Quinn; the Gardens by the Bay, in Singapore, among many others. From the last few years, the engineer has exhaustively studied about bamboo, its structural properties and its most diverse potential.

According to him, bamboo is close to the ideal structural material, beginning with its tubular shape. An open section, such as a channel, is weaker than a closed one because the edge can bend much more easily. Just think of a sheet of paper and how it becomes stronger when we roll it up like a tube, preventing it from bending so much.

In addition, it has another feature that improves its resistance. The bamboo culm has longitudinal fibers that span the entire lenght, called vascular bundles. Closer to the exterior of the culm wall, these bundles have a higher density, making them stronger. So, the stronger part of the section is further away radially from its centroids, making the overall section stronger. And this is the main difference compared to a wooden trunk, which has its strongest material in the center of its section. Another peculiarity is its speed of growth. Unlike hardwood, which can take more than 30 years to be exploited, bamboo can be cut and used between 3 to 5 years, then growing again.

In laboratory tests bamboo also achieves impressive structural capabilities. Its compressive strength is equivalent to concrete. Clearly, this can range according to the species – more than 1500, which grow naturally on almost all continents, especially in regions with higher temperatures.

Even so, there is some resistance to the use of the material, since it requires another type of thinking and the breaking of certain paradigms so rooted in architecture. One of them is the fear of using the material in its rough form, with its irregularities and natural forms, where the beauty of bamboo lives.

There are, of course, some issues that need to be considered, such as the chemical treatment of bamboo prior to its use for construction, to prevent rotting and insects infectation. Another issue when constructing with bamboo is the fact that its components should be very well protected from the sun and rain, for adequate durability. This also includes the pillars, which cannot be in direct contact with the ground. This is usually solved by adding a piece of rock over the shallow foundation.

The detailing of bamboo and its connections has been historically developed, being passed from one generation to the next through artisan builders, evolving through the understanding of the material itself. In the 21st century, with all the technology we have available, it is possible to better understand the specific forces in different conditions (strain, compression, bending, shear) and apply modern technologies, so that it is possible to optimize the material and to use other materials and techniques, such as shells and membranes, to achieve even more ambitious structures.

Neil concluded by stating that bamboo is the most sustainable natural building material on the planet and that we are certainly at the beginning of its use in a much broader way. However, his main teaching is that we should not try to adjust the bamboo to the existing rules, but change the rules to suit the bamboo.

By Eduardo Souza. Translated by Guilherme Carvalho.


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Arch Daily: How (And Why) to Integrate Earth and Bamboo Into Your Architectural Project

© José Tomás Franco

By recognizing and analyzing the multiple architectural possibilities of bamboo—a construction material mostly native to warm and tropical areas—the following questions arise: How can we take advantage of its qualities and enhance its use in colder climates? Such regions necessarily require a certain level of thermal isolation in walls, floors, and roofs—but for these climates, we can combine bamboo with materials that complement it.

We talked with Penny Livingston-Stark, a designer and professor of permaculture who has worked for 25 years in the field of regenerative design based on non-toxic natural materials, to understand the opportunities offered by combining bamboo with earth.

Earthen construction and bamboo are extremely compatible. They offer different capacities. They compliment each other beautifully. They both require the same conditions, like breathability.

Livingston-Stark insists on the compatibility of these two materials. Their similarities and differences help them to integrate remarkably well, increasing their architectural possibilities based on completely regenerative solutions that satisfying human needs while regenerating ecosystems. “Earth and bamboo are not compatible with plastic vapor barriers or paint, for example. I consider them to be living materials that need to breathe,” she adds.

© José Tomás Franco

Both materials are readily available throughout the planet and are non-toxic, low impact to the environment and can actually help regenerate ecosystems through their harvesting. For example, we can create ponds, wetlands or water retention structures on the land by where and how we harvest the earthen material. Bamboo sequesters a significant amount of atmospheric CO2 from the air by absorbing it into the stalk, roots, and leaves.

© José Tomás Franco


Bamboo offers structural tensile strength and can be used to support weight over long spans. Earthen walls offer either thermal mass to moderate extreme temperatures or insulation depending on the technique. Earth mixes well with all grasses. There is also virtually no waste in the construction process.

According to Livingston-Stark, bamboo gives certain added values to traditional construction with earth, such as tensile strength and the ability to hold weights over long spans such as roofs, wide doors, and windows. In addition, it expands the capabilities of existing earthen structural techniques, such as those using light straw clay, wood chip clay, or the “pajareke” technique.

The incorporation of bamboo into these traditional techniques was proven during the past Bamboo U course, held in November of 2017 in Bali, Indonesia.

© José Tomás Franco

For the experiment with “pajareke,” the students built a wall mixing clay dirt and water to make mud with a consistency similar to that of chocolate mousse. Then long straw fibers were covered with the mixture, and the wall built up between vertical bamboo poles that were rooted in the foundation of the building and tied in at the top. At the client’s request, short, horizontal pieces of bamboo were also added to allow ventilation through the wall, installing bamboo cylinders in a pattern to look like bubbles rising.

© José Tomás Franco
© José Tomás Franco

When testing the “Light Straw Clay” technique, a light mud and straw wall was built, mixing straw with a light clay slip (clay and water mixed to a thick paint consistency). The mixture was tamped between boards and bamboo poles, after which the boards were removed and a plaster of earth or lime was added, materials that are also very compatible with the two materials.

© José Tomás Franco
© José Tomás Franco

The “Wood Chip Clay” technique is similar to the previous one, but the mixture is made incorporating clay slip and bamboo chips. In this case, the boards containing the mixture are made of lath, and they remain in place to be plastered over.

© José Tomás Franco
© José Tomás Franco

Check out more details of Penny Livingston-Stark’s work and the Regenerative Design here.

As basic suggestions when integrating these two materials, it’s important to know the soil texture (ie, sand silt, clay content) and to make samples in advance of various mixes. Also, It’s important to think about the connections between the materials so they are tied in appropriately. Water and moisture protection combined with breathability should be considered.

© José Tomás Franco

By Jose Tomas Franco

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Arch Daily: Why Architectural Models Are Crucial in Making Bamboo Projects a Reality

Each material has its own peculiarities and, when using it for building, the design and construction process must accommodate these characteristics. A steel-framed building, for example, must be designed with a certain level of accuracy so that components and parts, usually manufactured off-site, fit together during assembly. A wooden building can have its cross sections drastically modified according to the species and strength of the wood used, or even according to the direction of the loads in relation to their fibers. With bamboo, no pole is exactly the same and each one tapers and curves differently, which requires a different approach when designing and building.

But how is it possible to work with a material with so many challenges and possibilities?

© Eduardo Souza

Building with bamboo requires, above all, a new way of thinking about the project and the work. According to Ewe Jin Low, a lead architect at IBUKU, “to learn how to build with bamboo, you must rather unlearn a little of architecture.” This does not mean that it is necessary to forget what you have learned during college, quite the contrary. It concerns understanding the material and respecting its peculiarities, its natural irregularity, the way it grew and even how it was cut. In other words, unlearning means leaving behind some preconceived ideas about architecture and admitting that a bamboo building will never be accurate to the millimeter, will never have perfectly round dimensions, and it is therefore impossible to think of it structurally as you would think of concrete or steel. A designer must take into account that a natural and raw material such as bamboo has memory, has differences in color, size, and strength—and therein lies its beauty.

Along with sketches and conceptual images for reference, models play a vital role in the design process of bamboo projects. As well as being very important during the design of a new building—in volumetric and structural studies—they are the main documentation of the projects developed by the IBUKU office. Generally created at a scale of 1:50 or 1:25, sticks are used which are scaled according to the sections of each species of bamboo to be used in the constructed building. When the design is finished, approved and ready for construction, two identical models are made. One goes to the site and the other stays in the office, in case of loss or breakage. What is more interesting is that the model, constructed in the same material, behaves structurally in the same way as the constructed building, and through it you can test issues such as structural spans. During construction, the model is often revisited so that dimensions can be verified, or doubts can be resolved.

© Eduardo Souza

The organic forms developed in IBUKU’s projects are generally best represented in scale models, where one can clearly see all the structural components and how they work together. The models are both a design element and a form of documentation for the construction. However, “traditional” technical drawings are also developed. Sections and floor plans are important, especially for the interiors, for the electrical and plumbing installations, and for sending to other professionals involved in the project.

During the Bamboo U course, participants were able to work with bamboo models, developing pre-designed models and also developing their creativity through their creations. In this way, they were able to better experience and understand the characteristics of bamboo, its elasticity, resistance, and potential. At the same time, a skilled model-maker was developing the final full-size construction model during the final days of the course with the help of the participants.

By Eduardo Souza. Translated by Jose Tomas Franco.

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Arch Daily: Learning Basic Bamboo Joinery With Indonesian Carpenters

© Eduardo Souza

The main objective of the BambooU build and design course is to promote bamboo as a green building material, and to provide tools to architects, designers, builders, engineers, and carpenters from all over the world to value this material and increase its use.

The 2017 version of the course invited its participants to be part of a basic carpentry workshop, in which Indonesian artisans—led by I Ketut Mokoh Sumerta—taught them to build the base of a simple structure in Bamboo, without using other materials and by experimenting with the cutting and joining of different pieces.

See the process of this construction below.

© Eduardo Souza

Well-dimensioned structural nodes are fundamental for the proper transmission of loads in a structure. In buildings constructed of natural materials such as wood or bamboo, this part requires attention and extra work during the execution. When adding materials such as steel to provide rigidity, this can improve structural performance, but also cause problems with differential contraction, or even oxidation, if proper precautions are not taken.

Bamboo, with its variety of section shapes and dimensions, requires connections that allow it to move, while accommodating its natural shapes. An example of a connection that is being continuously improved by the Indonesian people is the so-called fish mouth, which is constructed using bamboo alone and functions as a basic junction between beams and columns. With or without the help of power tools, it relies on the skill of the builders to create a detail that is strong, efficient and beautiful at the same time. To build it you need only a ruler or tape measure, pencil, a knife, a hacksaw, a chisel, and a drill.

© Eduardo Souza

The construction of the fish-mouth connection begins with a V-shaped cut in the column, which will accommodate the beam. This cut corresponds to the radius of the bamboo beam (or half of its diameter). It is important that the entire beam is touching the entire surface of the cut so that there is no weakness.

© Eduardo Souza

To lock the structural node, a hole is created in the beam, where a small section of bamboo is inserted. Ideally, this part should be cut so that there are no gaps and the lock is efficient. After this, the drill is used to create two holes where pins (also made of bamboo) are inserted, which allow the proper locking of the structure.

© Eduardo Souza

Still, in order to increase the stiffness of the joint, a third piece is inserted diagonally between the two pieces to connect them, with bamboo inserts and pins once again used for attachment.

Although it seems ingenious and complicated at first, the junction can be understood and executed after a few hours and allow the construction of bamboo structures. Only with a lot of practice is perfect execution possible. Knowing how to execute this basic detail, it is possible to imagine some variations, using other angles and changing the dimension of the pieces.

© Eduardo Souza

The most important lesson is that working with a natural material requires, above all, respect. And learning from old techniques that have already been tested and rethought is often a good step to success.

© Eduardo Souza

By AD Editorial Team