Bamboo must be properly prepared and cured before using it for joinery. Only mature, dry bamboo without cracks or insect damage should be used. Various cuts like one ear and fish mouth can be used to join bamboo pieces. Traditional bamboo joinery techniques include using nodes, dowels, anchors, wedges and splicing to connect horizontal and vertical bamboo elements. As bamboo becomes more widely used in construction, simplified and standardized joining systems still need development.

1. Bamboo Joints and Joinery
Techniques
Basic Principlesand Techniques
How to join bamboo and what are the best bamboo joints? Well first of, it is
important to know a few basics principles about joining bamboo before
discussing the different joinery techniques. So here goes...
 Do not use green, fresh cut bamboo. Bamboo has to be
completely dry before using it in construction (preferable air dried).
During the drying process the bamboo diameter shrinks, so when
bamboo is used in joinery this will result in lose and weak joints after a
few weeks.
 Do not use bamboo when it is less then 3 years of age. Only
use mature bamboo of 4-6 years.
 Do not use bamboo infected by insects (powder beetle for example).
Bamboo has to be properly cured with a boron mix immediately
after harvesting.
 Do not use bamboo that has flourished. Rest assured bamboo
only flourishes once in a lifetime (60-120 years).
 Do not use bamboo poles with profound vertical cracks.
 Use appropriate cuts and joints when building with bamboo.
 Use bamboo with the right diameter and wall thickness for your
project.

2.  Do not use conventional wood nails in bamboo joinery, they will cause
the bamboo to split. Instead use nylon, steel or vegetal cord of the
appropriate diameter.
 When using bamboo as a column make sure that the lower part
connecting with the surface ends with a node. If not the bamboo will
splinter when struck (for example to position the column).
 When connecting bamboo poles with bolts, make sure to bolt them
together in between 2 nodes, otherwise the bamboo may crush. More
about utilizing the nodes below...
Bamboo Has Nodes, Use Them!

3. In construction, using bamboo nodes is very important. Bamboo columns or
beams need to have a node at both ends (or as close as possible towards
the ends), if not the pressure of a structure on the joint may crush the
bamboo.
Often it isn't possible to find bamboo of the required length with both end
nodes in place. When this occurs you should insert a wooden cylinder of the
appropriate diameter or a fitting piece of bamboo with a node.
Bamboo Cuts

4. These are the most common cuts to use when making bamboo joints:
one ear / two ear / beveled / flute mouth / fish mouth
As you can see in the illustration below, making basic cuts in bamboo doesn't
require expensive or heavy power tools, just a few traditional hand tools will
work fine.
Bamboo Joinery Techniques
Making good and aesthetically pleasing bamboo joints is rather complicated
because bamboo is hollow, tapered, has nodes at varying distances, and
it is not perfectly circular. It is important to keep all these constraints in mind
when designing a bamboo joint.

5. Although traditions, local practices and publications give some information on
bamboo joinery, this information is far from complete as essential data is
missing in most cases. Many traditional joinery techniques suffer
from weakness or deformation, where the strength of the bamboo culm itself
is lost.
Before bamboo gets widely adopted in modern architecture (and
becomes affordable for all to use), the problem with bamboo joints and
universal joining systems has to be solved. After all, timber, steel, and more
recently prefabricated concrete, only became proper building materials for the
same reasons. How many cumbersome solutions for joints have one seen,
before these materials became a standard in construction?
Only if the problem with bamboo joinery can be satisfactorily addressed,
and simplified, we can expect to see much more bamboo in Western
buildings, bridges and furniture.
Below you'll find some examples and illustrations of traditional bamboo
joinery techniques.
Joining horizontal with vertical elements
1. Joint with one or two ears. Is used to join bamboo rafters, logs or lumber.
4. Flap joint. Is used when there is no lashing wire available. The flap can be
secured with bamboo strips.
5. Fish mouth joint.

6. Use of dowels and anchors in bamboo joinery
1. Joining bamboo with dowels and lashing. The peg should be placed in
the column parallel to the rafter.

7. 2. Fish mouth joint with pegs.
3. Bamboo joint with wooden anchor. Is also used inverted.
4. Bamboo joint with metal anchor. This technique Is used in various
positions.
Double and quadruple bamboo rafter support

8. 1. Beams formed by 4 or 6 members. The top row is separated from the
bottom with bamboo or wood slats so that the upper bamboos do not slide
over the lower.

9. 2. Central double rafter. It has a wide range of applications in the
construction of bridges and structures for rural facilities.
3. Lateral double rafter. Each of the rafters is secured independently at the
side support and each other. It is often used in the construction of bridges and
structures for rural facilities.
4. Lateral double rafters. Is often used as a central support for bridge
structures or sheds.
Joining and fixation of bamboo poles
1. Joint with double wooden wedge.
2. Joint with dowels and clamping fitters.

10. 3. Cross joint with dowel.
4. Lateral joint with dowel.
5. Corner joint.
Splicing bamboo poles

11. 1. Top splicing.

12. 2. Bevel splicing.
3. Ray splicing
4. Half bamboo splicing.
5. Splicing with internal union.
6. Splicing with external union.
7. Telescope splicing.
Source: Oscar Hidalgo Lopez, Manual de construcción con bambu.
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