Homestead Green Building: Bamboo

When you hear the word bamboo, what images flash through your mind?  Maybe a tropical paradise.  An open house where the warm breezes can easily come rushing through.  Not surprising.  Bamboo is used a lot in construction of homes and other buildings, but primarily in areas like Asia, islands of the Pacific, and, more recently, in Central and South America.  It's taking it's time coming into it's own here in the U.S. and other places.  But it is coming.  And for very good reason.  Let's look.

Bamboo might just be the master of disguise.  It is a grass.  It is one of, if not the, fastest growing woody plant on the planet.  Some species can grow more than three feet in a single day.  Generally, it comes to full growth within nine months to a year.  It can be stronger than steel, and yet is so flexible, that buildings made from it can withstand earthquakes and hurricanes.  And it is extremely flexible.  In it's full form, it can be used for walls and/or a support structure.  It can be cut in half, lengthwise, to create siding and flooring.  The fibers inside of it can be made into a natural insulation, or even into clothing.  It is a remarkable plant.

The downside of bamboo... well, that just depends on your perspective, I guess.  As a plant, it is extremely vulnerable to insects and mold unless it is treated as soon as it is harvested.  Once treated, it is, however, virtually impervious to these same issues.  You can grow your own.  Just be sure to make sure it is the best species for use in building, and that it can be grown in your climate.  (For a breakdown of best species for building, look here.)  There are some species that grow in more northern climates, but for the most part, bamboo prefers warmer, tropical regions.  For this reason, you may have to have your bamboo shipped in.  That can easily add up into quite the pretty penny.  If you are looking to keep your costs to a bare minimum, that is something you'd definitely have to consider.  Also, you should never use young stalks.  If you want the structure to last, the bamboo should be at least 3-4 years old and completely dried out prior to use.  Bamboo cannot be put together the same way you would a traditional timber-frame house.  Do not use nails.  The bamboo will split, and, result in a less than stable support.  It should either be lashed together using old world techniques, or possibly larger bolts, so long as they are used in the right ways at the right places.  Use the natural nodes of the bamboo. See here, here, and here for various joining techniques.

Most sources I've come across say that it can be used for homes in colder climates, so long as a double wall construction technique is used.  Basically, that means a two separate bamboo walls, an exterior and an interior, with some sort of insulation in between.  This source, however, says that there is a concern of fluctuating temperatures and humidity levels causing the bamboo to crack.  That is something important that would need further clarification from a certified builder if you are looking to build in a colder climate.

As for building codes, here in the U.S., I've not been able to find any information on current updates to codes that cover using bamboo as the primary construction framework.  That's not to say that it's not out there, I've just not been able to find it.  And, as so many areas have varying codes, not just from state to state, but also from county to county, and sometimes even from town to town, you want to make sure that you have all the answers you need before making the jump into building with bamboo.  Make sure to contact your building authority to find out exactly what the specifics are.  Or, you may be able to contact a local architect or builder that specializes in green home construction. They may be a bit easier to get information out of, as many code enforcement offices can be quite hesitant when it comes to green construction.

Now, when it comes to insulation, if you don't need much, you can use the bamboo in and of itself, as the natural hollow core creates a "dead air" space.  That space creates a measure of insulation, although maybe not much.  (I haven't been able to find anything relating to an R value.)  However, if more is needed, you can use the double wall technique and fill with the insulation of your choice.  There are manufacturers of bamboo insulation, but most of them are overseas.  So, again, shipping costs will play a part in your decision there.

Bamboo is a beautiful and sustainable building material.  If you don't have a supplier close, or cannot grow it yourself, it can get a bit on the expensive side.  But it is flexible enough to be able to be used in almost every aspect of the building process.  It is a product that has great potential.  A time may come when it is more readily available and costs will drop.  For now, I would say that the cost is the primary hindrance that would keep me from using this amazing plant.  I leave you with a collection of informative sites from people more knowledgeable than I, that may be able to answer more questions you may have concerning utilizing bamboo in construction, as well as new and upcoming development ideas for uses of bamboo.

http://inhabitat.com/beautiful-bamboo-living-houses-take-two-days-to-build/

http://webecoist.momtastic.com/2011/06/20/building-with-bamboo-13-super-sustainable-structures/

http://www.greenhomebuilding.com/bamboo.htm

http://www.bamboogrove.com/bamboo-houses.html

http://www.communityarchitectsnetwork.info/upload/opensources/public/file_14062013022345.pdf

http://www.ehow.com/how_4613878_build-bamboo-house.html

https://www.niftyhomestead.com/blog/bamboo-buildings/

https://www.dezeen.com/2015/11/04/bamboo-fibre-stronger-than-steel-dirk-hebel-world-architecture-festival-2015/

http://www.jeccomposites.com/knowledge/international-composites-news/development-bamboo-fiber-composites-china

http://news.mit.edu/2014/researchers-study-bamboo-for-engineered-building-material-0723

http://ceramics.org/ceramic-tech-today/biomaterials/could-a-bamboo-fiber-composite-replace-steel-reinforcements-in-concrete

http://www.mse.umd.edu/sites/default/files/documents/undergrad/enma490/Team%20Bamboo%20Fiber%20Composite-Report.pdf

http://www.ripublication.com/ijcer_spl/ijcerv5n3spl_08.pdf

http://www.resource-fiber.com/why-bamboo

http://design490.org/bamboo-the-new-building-material/

https://www.researchgate.net/publication/229140175_Bamboo_fibre_reinforced_biocomposites_A_review

http://www.sciencedirect.com/science/article/pii/S0261306914005135

http://engineering.stackexchange.com/questions/10477/steel-vs-bamboo-strengths-in-various-directions-orientations-tensile-compres

http://www.newsweek.com/stronger-steel-85533

http://www.archdaily.com/513736/bamboo-a-viable-alternative-to-steel-reinforcement