Safe and secureEarthbag building techniques may be the best way to ensure disaster resistant homes in rural Nepal
The proper handling of a natural disaster requires the implementation of several absolutely essential steps. It begins with the realisation of disaster-resistant construction in disaster prone areas, followed by proper and timely evacuation before the disaster. In the aftermath of the disaster, an efficient strategic system, preferably in form of an official government agency that helps coordination and distribution of relief aid is crucial. Up until recently, the Nepal government has been lacking immensely in every single one of these steps and has done the minimum to ensure the safety and security of its citizens. Now, the government has taken a few steps into the right direction, remarking recently that flood-resistant houses in flood prone districts will be build in the next six months. The pertinent question here is: Which construction technique would be most suitable for rebuilding?
The actual problem is that, in the rural regions of Nepal, most houses are constructed without any engineering input—no building codes are followed. Impoverished families save costs by cutting down on proper materials, labour and design—traditionally applying materials that cannot withstand natural disasters (such as floods or earthquakes) like mud and straw. This triggers an endless cycle of rebuilding homes that are highly susceptible to natural disasters.
In my previous article, I mentioned how people in disaster-prone districts needed sophisticated training in the construction of disaster-resistant housing. A relatively new, and easy to adapt, technology that has just recently been approved by the Department of Urban Development and Building Construction would be the best bet for stable and economical building. The construction technique is called
Economical and secure
Earthquakes are shock waves. The effect of shock occurs when the energy of an impact is transferred from one object to another. Typically, structural parts of a house are all interconnected, making the whole building move during an earthquake. But in the case of earthbag construction, the foundation is not directly connected with the structure. Lose rubbles used as the foundation result in the houses functioning as a shock absorber. Bags filled with gravel, with one layer underneath the ground and two layers above, are stacked on top of the rubble trench foundation. On top of these is the key component for the houses: the Earth bags.
Soil—mostly sand and clay—is stuffed inside polypropylene bags, which are staggered like masonry blocks and solidly tampered. Letting sand and clay dry after applying moisture to it makes it a very hard substance, and if the polypropylene bags are plastered properly the construction can last for hundreds of years. Between the bags barbed wire, instead of cement, is used for connection, stabilisation and tensile strength. The exterior is then plastered with a cement base coat. This also makes the earthbag construction withstand flood. Due to the natural property of earth, the house additionally serves as a cooling system in the summer and keeps you warm during winter. The roof can be of any design, to the homeowner’s preference, as long as it is lightweight. A budget analysis shows that 86 percent of the total budget stays locally. Out of the 86 percent, 30 percent is labour—which is comprised of volunteers and members of the communities themselves. 56 percent of the materials stay locally, meaning it’s free. Use of local materials lower the need for transportation and reduce fuel costs. Building with soil means fewer factories and smoke stacks, fewer pollution-belching trucks for transporting the load, and less depletion of Nepal’s forests and natural resources. Building with earthbags is very inexpensive, with costs ranging around Rs900 per square foot, versus Rs2500 for concrete block construction.
What is encouraging about building with earthbags is that it has earned its safe and disaster resistant tagline from the most rugged of tests. Before the 2015 earthquake, there were 55 earthbag constructed buildings in Nepal. All 55 buildings, survived the 7.8 magnitude earthquake with no structural damage whatsoever.
NGOs, such as Good Earth Global, Steadfast Nepal and First Steps Himalaya have been implementing the earthbag technique to build homes and schools since after the 2015 earthquake that rocked the nation and destroyed many homes and schools. After a two year struggle, Good Earth recently managed to make Nepal the first country in the world to officially approve of earthbag technology and adopt it as a safe and recommended building technique. In a competition organized by the Nepal Engineer’s Association, Good Earth received the award for “Best Rural Design.” Earthbag technology is not a new invention; people have been benefiting from its principles for at least a century. However, it is great to see organizations and the Nepali government working to institutionalise earthbag designs and to make earthbag building techniques more accessible.
At present, there are over 15,000 earthbag buildings worldwide, with recent earthbag constructions gaining approval under strict US building codes. In Nepal, if this project keeps being integrated throughout the country, I can definitely see it transforming Nepal’s culture and way of life in the future by changing the way rural homes are built. If the government is serious about their recently announced plan to ensure disaster-resistant housing for disaster prone areas, incorporating earthbag technology should be on the top of their list, and more should be done to promote its benefits.
- Ahey is pursuing a Bachelor’s degree in Social Science from the University of Nuremburg, German