Travelling to far off places opens our eyes and options exponentially, and makes us apply the new learnings locally, back home. From this perspective seeing houses completely built with bamboo can be an exciting proposition and there are many of them in varied regions of India. However, suddenly jumping into the dream of doing a bamboo house in Bangalore or Chennai will not be easy. Local materiality and construction practice always holds fort and discourages new ideas from pouring in.
In such cases, introducing bamboo step by step, slowly expanding to more elements could be an easier way out. Since we have extensive bamboo constructions as a proof for their performance, even in heavy sun or rainy regions, having some certain building parts may not become a bothersome issue. Of course, proper treatment with Boric acid Borax solution or gentle burning or seasoning with flowing water and such other measures for reducing the sap content, to keep it well seasoned is a pre-requisite. Also, we need to follow basic code of practice like avoiding poles with visible splits and such others.
Pavilions are amongst the easiest to start with bamboo in any building. Like any other roof, it needs column support done with 6 inches or larger diameter poles, or if spans are longer, we may use structural steel as advised by the engineers. Such members can even be wrapped with bamboo peels skinned from its outer surface to give the looks of bamboo. Machine pressed bamboo mat, hand woven mats or local regular mats could be used as ceiling finish, supported on split bamboo. Thereupon, coated G.I. sheets, water proof thick plastic or any other metal roofing can be laid to ensure protection from rain. Incidentally, traditional homes achieved it without metal anywhere!
The top is finished with small bamboo poles or sometimes, with half split bamboo laid with the curved part upwards. When tin sheets became popular, they replaced the bamboo top, considering complete bamboo roof is more cumbersome and maintenance heavy when it comes to rain protection. However, they deny the bamboo looks – an aspect many people prefer to see, hence the idea of composite roof with both sheets and bamboo. Being lightweight roof, bamboo pavilions need lesser cost for support members.
Bamboo members should not run across the slope, obstructing the flow of rain water. Point of contact between metal inside and bamboo top can hold water dampness affecting both the materials, hence pre-treatments are mandatory. The mat between the rafter supports may sag as people work on it or by age, hence proper spacing should be maintained between the supports.
The pavilion idea can be easily extended into a room itself with bamboo pole flooring support, floor finish of one’s choice, better security and rain protection. If we have the desire to start with bamboo, it is not difficult to end with a bamboo house.