Bamboo construction has a long history of being used for inexpensive and short-term structures in regions to which it’s native, but only recently have we started to see bamboo used for long-lasting, large-scale projects. It is estimated that nearly one billion people around the world in places like Southeast Asia, South America, and West Africa live in dwellings that are largely composed of bamboo, and large bamboo projects have been constructed in the past, such as the bridge on the island of Java seen below.
Bamboo has impressive structural capabilities, as it has the tensile strength of steel and the compressive strength of concrete while being lighter than both of these conventional Western materials. With its hollow core, intermittent nodes, and a usable length of up to nearly 60 feet in select species, it is inherently elastic and can form complex geometries and breathtaking architecture. However, for a long time bamboo was seen as an undesirable building material only for those in poor and rural areas because even small amounts of damage from beetles, termites, and rot from excessive moisture can ruin the material in as quickly as one year. With modern treatment methods using borax, a naturally occurring salt-based compound, bamboo has now become a viable structural material with an increased lifespan of about fifty years. Pioneering firms like Changmai Life Architects, IBUKU, Vo Trong Nghia Architects, SUP Atelier, and many others are showcasing the incredible possibilities of twenty-first century bamboo architecture.
In 2018, Chiangmai Life Architects’ Bamboo Sports Hall at Panyaden International School in Chiang Mai, Thailand was completed, showcasing the potential for increasingly long structural spans through the use of arching bamboo trusses. These trusses were built on site and lifted into place by a crane, and they span 56 feet without any steel reinforcements. As bamboo naturally serves as a carbon sink, the project has a net zero carbon footprint, with the bamboo used having absorbed more carbon than than the amount of carbon emitted during treatment, transportation, and construction. A variety of diameters of bamboo are strategically used throughout the project, with bundles of smaller bamboo serving to create the curved forms, and the larger bamboo serving as stiffening elements within the trusses and at the exterior walls.
The Sharma Springs residence designed by Bali-based firm IBUKU is the tallest bamboo structure in Bali and showcases bamboo construction in a luxury residential context. Standing at 75 feet tall, the house features large lotus petal-shaped roofs that work to invite cross-ventilation throughout the primarily open-air home and is spatially organized around a vertical circulation core with a viewing tower at the topmost level. Nearly all of the structural elements and finishes are bamboo, with the assistance of steel connection points and thousands of bamboo pins that help hold the individual members in place.
The use of “lidi bundles” is a notable strategy for the structure, which involves tightly tying together thin bamboo strips that can bend easily in order to create custom curves. The firm’s projects involve physical model-making to explore and finesse both formal elements and structural systems, and along with drawing sets, a scale model serving as a three-dimensional blueprint lives on the project sites to help guide the construction and bespoke craftsmanship.
Structural design codes for bamboo architecture were published only quite recently in 2004, while formal research into the optimal applications for the approximately 1,400 bamboo species is essentially just beginning. With most architects worldwide having limited to no knowledge of standard practices for bamboo, it is seldom specified as anything other than a finish material; however, this could change with increased education and research into the abundant environmental, structural, and phenomenological benefits of the material.
Written by Kristin Fauske
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