november 2015
Bamboo is a resource hardly known in the industrialized world, that can help sustain our use of materials: its biobased and has a larger yield per functional service as for instance wood. Besides, many developing countries have large bamboo forests, and could use this resource. Which, of course, they do. Around 1 billion people live in bamboo based houses. But this is constructed from the raw culm.
For some years I have been involved in bamboo research for constructional use, but in modified form: laminated bamboo and /or strand woven bamboo. This makes it possible to standardize sizes, and copy the timber frame construction approach. It leads to higher performance constructions, compared to the standards in industrialized world. Its also a way to help fight climate change, since when 1 billion people become more wealthy, they will favor to build “ a modern house”. Usually made from concrete steel and glass, and high impact. With structural modified bamboo, in potential they can have a “modern house” but with a core construction from Bamboo. Limiting the embodied impacts from new housing . Its interesting to see that after 30 years of concrete construction in China, now the mood is changing and demand for wood and bamboo houses is growing again. Which relates very much to their cultural history, their architecture is originally wood and bamboo based.
And of course modified Bamboo can even more reduce impacts when used in our industrialised world, and might be welcome when other materials will become less popular due to CO2 caps and credits, put in place during COP21 ( lets hope…) .
So far there were only few examples of constructional use of modern modified bamboo, mostly test and demonstration projects. One reason being hardly any country had regulations for this. Which again was caused by the fact that hardly any research with reliable data was available. In most countries it is not regarded as wood (formally it’s a grass) , so it needs separate regulation.
This is changing: Colombia, Peru and Ecuador now have official building regulations for bamboo construction. Mainly for laminated bamboo: bamboo poles are sawed into small slats, glued together for beams and panels.
China is aiming also for construction regulation with bamboo, but more focused on SWB5G, the type we are researching in cooperation with the Chinese Academy of Forestry: Strand woven bamboo 5th generation: which is a process in which hardly any material is lost: The bamboo poles are flattened and crushed under a few cylinder drums , and then compressed in rectangular forms with glue, to come out as beams and panels. It is a very strong in some cases nearing steel. The embodied energy impacts are much lower, and the yields very high. More will be published on this. A first test houses was built near Hangzhou in China..
What I did not know was that laminated bamboo , normally used for furniture, and wall cladding so far, was already used for constructional use. I was informed by Edwin Zea, A PhD candidate who I supervise and does bamboo research, (defending his thesis in December in Zurich,) . Via his links I found a beautiful example as a community Centre in China. See below websites for for more details. Constructive use of bamboo is surely taken of, things develop fast and will conquer the (construction) world the next decades. ( More In December)
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pictures:
1st: demohouse SWB5G, Huangzhou China
2nd: community centre Cifeng Village Sichuan Province China
see
http://en.cctf.org.cn/html/2012-11/180.html
and
http://openbuildings.com/buildings/kpmg-cctf-community-centre-profile-5437
