Bamboo is a great material to use in construction and after learning a few basic techniques, it can be really easy to build with as well.
It grows abundantly throughout many areas of the world, can be harvested easily and once treated, can last a long time. The only problem is, there is not much information out there on how to actually build with this amazing plant.
I have built a few structures of my own out of bamboo, travelled throughout Indonesia and worked with local craftsmen and have taken a bamboo building course with BambooU, which I highly recommend. If you are looking to learn how to build with it, you’ve come to the right place.
What Type Of Bamboo Is Best For Building
In order to use bamboo for construction, it is important to use varieties of bamboo that are suitable to build with. Some varieties of bamboo are great for structural poles, others would be better used as wall material.
If you do not know what types you have, you can always perform an engineering test to see what types of loads they can handle.
Here are some of my favorite types to use when constructing a building.
- Dendrocalamus asper – Great species of bamboo to use for structural members of a building. This Bamboo can reach almost 8” in diameter!
- Dendrocalamus asper f. Niger – Same as the bamboo above, except this one is black!
- Gigantochloa apus – Great for use as scaffolding or rafters
- Gigantochloa atroviolacea – Same as Gigantochloa Apus except this one is black
- Bambusa blumeana – This thorny bamboo is very strong and great for construction, but has a hard time growing straight and in Hawai’i it tends to be attacked by powder post beetles quicker than any other species.
- Bambusa Oldhamii – I have this one growing in my yard. It can get to about 4-5 inches in diameter, grows long and straight and is pretty thick walled. I like to use it for rafters or other non structural elements in a building
- Thyrsostachys siamensis – great for use in interior non load bearing applications
- Phyllosatchys aurea – This is one of the most common bamboo in the US and also one of the most invasive, so why not build with it! It is a running bamboo that spreads easily but can be used for detail interior work or as non load bearing lumber
- Bambusa vulgaris – Very common, strong clumping bamboo that grows almost everywhere in Hawai’i. This bamboo can be good for load bearing poles, but best where large non load bearing poles would be needed.
Treating Bamboo So It Lasts For Decades
Most people will claim that bamboo doesn’t last long, which is true if your bamboo isn’t treated. But by treating bamboo, it is possible to make it last decades!
Methods for treating bamboo include heat treatment, pressure treating, soaking, or through vertical soak diffusion with a borax/boric acid mix. Treating bamboo with a borax/boric acid solution replaces the edible starches that insects love with an inedible concoction that poisons them instead.
On my travels in Indonesia, I saw many amazing bamboo buildings that blew my mind away. When I heard that some of them were over 30 years old with others known to be much longer I was amazed. I was always told how bamboo does not last, but experience told me that was not the case.
If you do want to learn more about how to treat bamboo, check out this other post explaining exactly how to do it.
Bamboo Building Begins With A Model
Before you even begin harvesting bamboo, it would be a good idea to make a scale model of the project that you have in mind. By doing this you can not only work out the design, but also have an easier time compiling exactly what you need for your project.
All you really need is some cardboard, bamboo skewers, a couple sushi roll makers and a hot glue gun. I like to take apart the sushi roll makers and harvest the bamboo pieces that it is made of.
Then I take those pieces of bamboo, measure them to scale and begin to build my design in miniature, gluing each piece along the way. This makes the actual building of the structure so much easier.
If you want to learn more about design bamboo buildings by making models then turning them into real life bamboo projects, you should definitely check out BambooU and their new online course on Building with Bamboo.
Tools To Build With Bamboo
The great thing about building with bamboo is that the tools that you need do not have to be too sophisticated. Most of it could be done with a hand saw, chisel and mallet. But with the right tools you can make building with bamboo go a lot faster.
Below is a list of my favorite tools to use when building with bamboo. Start adding them to your collection now so that you have them ready when it comes time to build.
- Circular Saw or Hand Saw
- Bamboo Splitting Knife
- 4x Bamboo Splitter
- 6x Bamboo Splitter
- Power Drill, Corded or Cordless
- Various Sized Hole Saws or Chisels
- ⅜” -½” Drill Bit, 6”-8” Long
- Mallet or Hammer
- Bamboo Carving Knife
- Orbital Sander
Foundations For Bamboo Construction
The first and most important step of any construction project is to give it a set of good boots, or a strong foundation.
With bamboo, a typical foundation consists of a concrete piling footing with a piece of rebar sticking out of it. The bottom nodes of the bamboo are opened up and placed over the rebar on the concrete footing, about 2 nodes up is good.
Two holes are drilled into the sides of the bottom nodes of the bamboo in which a liquid concrete can be poured into and allowed to harden. This has proven to be the best foundation system for a bamboo home. Think post and pier, except with bamboo.
Basic Joints Used In Bamboo Construction
Bamboo construction is inherently different for normal stick frame construction. Due to its round nature, bamboo must be treated differently than dimensional lumber. You can’t just nail two pieces together and call it good.
Bamboo requires specialized joints to join two pieces together, but don’t worry, once you learn them, they’re almost as easy as any other connection you’d make with typical lumber.
Some of the most common joints used in bamboo construction are:
- Fish Mouth Joint
- Modified Fish Mouth Joint
- Angle Joint
Fish Mount Joint
The Fish Mouth Joint is a common joint used in bamboo construction. It is named fish mouth joint for how the vertical bamboo member “bites” into the horizontal Bamboo member. It can be a tricky joint to make, but once you understand it, it becomes a lot easier to make.
A fish mouth joint is traditionally made with a hand saw, round chisel and a carving knife, but I have had good luck using various sized hole saws to do the bulk of the work for me and then I finish it up with a carving knife.
Once the mouth is made, it rests under the horizontal piece of bamboo and is pegged together with a wooden dowel. Sometimes this joint can be a little hard to make 100% secure, so a modified version has been developed.
To learn more about making a Fish Mouth Joint, Check out this post by Bamboo U.
Modified Fish Mouth Joint
Similar to the Fish mouth joint, this joint utilizes a smaller diameter piece of bamboo that fits inside the vertical piece of bamboo and into a hole drilled into the horizontal piece of bamboo. The two pieces are fit together and then bamboo pegs are used to secure it.
The smaller piece of bamboo allows for more contact between the bamboo pegs and the bamboo fish mouth to ensure a stronger connection. When I build my bamboo structures, this is my goto joint whenever a fishmouth is needed.
One of the strongest geometric shapes that we use to ensure rigidity in our buildings is a triangle. The angle joint is what we use to ensure that our buildings have shear strength, in other words, they help keep the building from feeling all shaky.
Essentially you are adding a piece of bamboo at a 45 degree angle between a horizontal and vertical piece of bamboo. A modified fish mouth joint is used on both sides of the angle piece and connected to the vertical and horizontal pieces of bamboo with bamboo pegs.
I probably use too many of these when I build, I just don’t like anything to be moving around on me.
Joint Connections With Bamboo Pegs, Nuts & Bolts, & Lashing
I have been mentioning Bamboo pegs in regards to securing joints used in bamboo construction, but there are a few other methods to secure your joints that you make when building with bamboo.
But first, what are bamboo pegs? Bamboo pegs are like thick chopsticks, typically carved by hand and used in place of nails in bamboo construction. They are the predominant way to join two pieces of bamboo together and secure them down.
However, when there is a heavier or structural load on a joint or where two pieces of bamboo comes together, a ⅜” bolt with appropriate sized nuts would be a stronger alternative. I only use these when strength is of utmost necessity.
Lastly, you may have seen many bamboo projects lashed together with twine. This is another great way to secure two pieces of bamboo together, especially when they are resting on top of each other rather than when a joint is made where 2 bamboo pieces fit together with a hole.
Lashing does take a lot of time and is important to be lashed correctly, otherwise you have a loose joint. It is hard to find bamboo lashing rope, so most of the time I use small diameter paracord.
Processing Bamboo To Make Splits, Planks and Roof Tiles
So far we have covered aspects of framing with bamboo, but what about wall panels and roof systems? Well, this is where things get a little tricky.
Wall panels in a bamboo home tend to be a little difficult to make where air gaps are not prevalent throughout the building. Bamboo can be split to create woven bamboo panels that can be attached to walls, or used as part of a wattle and daub wall system where bamboo is woven into the wall cavity and plastered over with clay or concrete.
Bamboo can also be flattened to construct bamboo roof tiles. These are great when trying to roof a building that has many curves as flattened bamboo is able to mold well with curvature. You can also use bamboo halves like spanish tiles to make a waterproof roof out of bamboo, though these tend to collect debris and mold easily.
You can also use metal roofing a top of your bamboo structure. It is not as pretty but will last you a long time.
Legalities Of Building With Bamboo
As you can see, bamboo is a great material for building with. All we need now is for it to be legalized to be used in constructing homes, especially in tropical environments.
Currently, bamboo can be used to build non-permitted structures such as gazebos, shade structures, furniture and so on.
With the ever increasing prices of lumber and the immense environmental damage that clear cutting has on an environment, hopefully bamboo will find a way to make it as a building material of the future.