Laminated Bamboo Process
I’d like to take a minute to talk about green materials, in particular laminated bamboo board. Engineered bamboo products result from processing the raw bamboo culm into a laminated composite, similar to glue-laminated timber products.
Many people think that this material is green, because it’s based from bamboo which is a rapidly renewable resource.
While it is true that the bamboo material harvested to go into laminate board product is just 3 to 4 years old, and bamboo is undisputedly a green material, the production process, additional chemicals, and energy consumption must also be accounted for in the green equation.
A couple of decades ago this material was my passion and for a few years, pioneering the production of laminated bamboo became the focus of my life. I was enthralled by the potential of coming up with a sustainable alternative to hardwoods.
I moved to Vietnam in 1995 and set up the first laminated bamboo panel production line, we made wood from bamboo, as well as more finished products from it such as furniture, houses and tongue & groove bamboo flooring.
I’ve had first-hand experience manufacturing this material over several years, and at a certain point ceased to work with it anymore as I became fully aware of all the environmental negatives that are the reality of producing it.
PRODUCTION PROCESS positives:
Partly comprised of a rapidly renewable material
PRODUCTION PROCESS negatives:
Excessive Machining, energy use, maintenance, carbide steel use and sharpening.
High Energy consumption from motors and machines.
Excessive Waste of unused bamboo parts and sawdust
Use of much Glue, especially urea formaldehyde.
Machining results in much glue and sawdust waste
More intensive Finishing, Excessive use of chemicals
Transportation great distances within and from China
First poles are harvested, the branches and top are cut off, and the poles are transported from the forest to a road. They are loaded onto a truck, and trucked to a pre-production facility.
The poles are split lengthwise into strips, these are called Raw Splits. These splits are soaked in preservative chemicals, and left to dry, either outside, or they are dried by using gas power or by burning any kind of combustible.
The splits must be machined perfectly rectangular. The machine used is a four-sided molder. This machine employs multiple cutter heads upon which many high-speed carbon steel blades are secured.
Because of the high silica content in the bamboo, the blades dull very quickly, so another machine which requires a lot of electricity, a carbide blade sharpener is required to run basically around-the-clock to maintain the cutter heads.
Each cutter-head is driven by very large electric motors. About 50% of the material of the split is removed and turned into sawdust and chips as the four sides get shaped (half the bamboo is wasted)
A very large and powerful dust extraction system is used to suck the waste material out of the 4-sided molder.
Energy consumption from motors and machines required to process this material must be considered “Green”. Energy, fuel, and pollution required to dry the splits also needs to be considered “Green”.
Billions of splits need to be glued together face to face and the glue that is most often used is urea-formaldehyde glue. Health effects occur when urea-formaldehyde based materials and products release formaldehyde into the air. UF glues can cause the onset of respiratory irritation and other health effects, and even increased cancer risk. It triggers watery eyes, nose irritations, wheezing and coughing, fatigue, skin rash, severe allergic reactions, burning sensations in the eyes and throat, nausea, and difficulty in breathing in some humans. Irritation of the mucous membranes (specifically the eyes, nose, and throat) is a common upper respiratory tract symptom related to formaldehyde exposure.
One of the little-known truths of manufacturing laminated bamboo, is that the amount of glue and cost of the glue is greater than the amount and cost of the bamboo used. YES, more glue than Bamboo!
After one layer has been glued and the glue has cured, it is a goopy glue encrusted mess, so it must get machined again to flatten the two faces. Now we are creating sawdust mixed with glue, where does this go? Good question!
Usually Bamboo flooring is multiple layers, quite often three, so this process is done three times, then the three boards are glued together, and then once again it will be shaped creating lots of sawdust mixed with glue.
If it is going to become flooring, then further machining, specifically tongue and groove must be performed.
I’ve been finishing wood my whole life, and finishing laminated bamboo for a considerable portion of it. Finishes are made of chemicals suspended in thinner, and the process to do it is applying a coat, and then sanding it, repeating this process multiple times until a nice coat has been built up. Bamboo absorbs much more finish than wood, and requires more coats to build up a nice sheen. So basically, bamboo requires more finish, more energy (sanding) and releases more airborne pollutants in the finishing process.
To say that it is bamboo, that it is sustainable, and that it is better than wood is a falsehood when considering what goes into making it.
“Because of the very efficient employment of labor in China, one would expect this country to be able to produce bamboo with the most efficiency and sustainability. It was surprising, therefore, that China’s production of bamboo is the least sustainable among the countries studied. This ranking was based on the ratio between output and environmental impact. It considered the very important, yet often neglected, fact that efficiency does not necessarily represent sustainability; just because a process consumes less does not necessarily mean that what is consumed can be recovered.”
Source - http://www-unix.ecs.umass.edu/~arwade/bamboo-review.pdf
Transportation is always a factor when considering how sustainable a product is. Trucking or shipping Bamboo over long distances should be considered when calculating sustainability.
“The vast majority of bamboo’s environmental load/cost was seen to be associated with transportation; assuming 1 kg bamboo culm, including transport from Costa Rica to the Netherlands as part of the production process, the load resulting from land and sea transportation was found to be approximately two times and 29 times greater than that of processing the material, respectively. It is important to note that these numbers compare total magnitudes particular to the study and do not imply, for instance, that sea transport is less efficient than land transport. “
Source - http://www-unix.ecs.umass.edu/~arwade/bamboo-review.pdf
By using a material that is sustainable, companies around the world are banking on the sustainability and hiding the facts about the process in which these products are made.
While there are companies that are producing laminated bamboo products with an eco-friendly adhesive the choices are limited and difficult to verify. Especially because a very high percentage of laminated bamboo comes from China.
We recommend buying bamboo products that have not been over manufactured. There are many ways to get creative with solid pole bamboo products. Have a look at our sister company boohugger
Having spent my entire professional life working with bamboo, I would be the last person to bash bamboo as a material, but I have had first-hand experience manufacturing “engineered” bamboo for several years, and I can tell you without a doubt that processed laminated bamboo is far less green then people marketing it would like to have you think.
I was so excited about this material when I started working with it, but when I really ask myself how green is was, the answer is apparent in the shift I took with my career to not work with it any longer.
Bamboo itself is amazing, it’s incredibly strong, vastly useful, and only requires sunlight and water to grow. That is incredible, and we can make so many awesome and practical things from it. Using it in the state closest to it’s originally grown form, yes, a pole, really is the greenest way to employ this material.
Sustainable Bamboo Products
Development of Laminated Bamboo Lumber: Review of Processing, Performance, and Economical Considerations M. Mahdavi1 ; P. L. Clouston, A.M.ASCE2 ; and S. R. Arwade, A.M.ASCE3 http://www-unix.ecs.umass.edu/~arwade/bamboo-review.pdf