Implication in Energy Of Performance in Post-Disaster Housing Reconstruction.

Abstract

The natural disaster does not come with notice. With many natural disasters for instance earthquakes, flood, landslides, tsunamis, and bushfires destroying human settlement around the world, post-disaster housing reconstruction has become a critical topic all around the world. The current practice of post-disaster reconstruction consists of various approaches that carry affected homeowners from temporary shelters to permanent housing. While temporary shelters may provide within a matter of days as immediate disaster relief, a permanent housing can take years to complete. However, time is critical, as affected communities will need to restore their livelihoods as soon as possible. (Jha, Barenstein, Phelps, Pittet, & Sena, 2010) While providing the settlement for the victims it seems that all other factors have been compromised a lot. Even in our case in Nepal after earthquake 2015 lots of NGO’s and INGO’s have done lots of reconstruction of housing without consideration of culture of that community, the climatology of the place, and so on. Which is directly affecting the energy performance of the building. As there are, a lot of thought has given after a long hit and trial process in a traditional building that is not considered in new reconstruction building that is making a trouble for people to live in their daily life as it was before. Therefore, this paper is intended to study the energy shift in post-disaster housing reconstruction from the traditional building.

Introduction

The world where we live in is full of natural hazards, both natural and manmade. Such hazards cause a destruction of habitats. While responses varied by countries, depending on their population, wealth and culture; and while the magnitude of disaster has also varied, as does the capacity for a country to respond, each country strives to restore its infrastructure to at least its original state. Following a major disaster, however, conventional project management is not applicable to disaster recovery projects.

Disaster-affected regions may face resourcing problems, such as shortages of building materials, lack of builders, market inflation, and increased cost of rebuilding, all of which can translate into frustration for communities as they attempt to recover. Massive resource shortfalls arise because of disaster impacts on markets and normal procurement systems.

Nepal has faced a massive destruction during devastating earthquakes also called Gorkha earthquake of 25 April and 12 May 2015. The earthquake was caused by a sudden thrust, or release of built-up stress, along with the major fault line where the Indian Plate, carrying India, is slowly diving underneath the Eurasian Plate, carrying much of Europe and Asia. About 9,000 people were killed, many thousands more were injured and more than 600,000 structures in Kathmandu and other nearby towns is either damage or destroys. The earthquake produced landslides that devastated rural villages and some of the most densely populated parts of the city of Kathmandu. About 68% of housing destruction occurred in rural areas of Nepal. Despite a prompt and extraordinary response in the immediate months following the earthquakes by the people of Nepal, the recovery and reconstruction process is not an easy task to initiate.

Post-disaster reconstruction of housing following a disaster is a continuous process, which begins immediately after the disaster and carried out for several years. Post-disaster housing reconstruction may suffer from the deficiencies in resources. The resource shortages in the aftermath of a disaster can trigger economic and environmental impacts on the affected areas in any country. The success of resourcing depends on multi-stakeholder collaboration and the development of policies, plans, and tools to allow market flexibility, donor management, and government intervention. At the same time, affordable housing is also persistent and worldwide imperative. Post-disaster recovery goals demand that this is accomplished using community processes and that new structures are better and stronger, will mitigate damage from future events and will be culturally appropriate (Berke et al, 1993; Comerio, 1998; Kennedy et al, 2008). Common strategies to respond to this need include a subsidy, reducing quality, simplification, and self-help (Katz et al, 2003; Johnson, 2006; Thorns, 2006; FAS 2008a; Gurran et al, 2008).

Relief construction process includes different steps that follow. They are a response, recover, and development stage. The government immediately takes these steps after a disaster with the help of humanitarian and development agencies. In the recovery, stage of post-disaster reconstruction, the important parameters like social, economic, and climatic, emotional values have not been addressed. In urban areas, the disaster relief process is much more complex in comparison to a rural area. This is due to larger scale of social structure and population as well as more concentrates reconstruction to be tailor to urban reality.

The major challenge after the disaster involves constructing or repairing the traditional houses. They have recovered or reconstructed using cement and concrete - granting little or no attention to the conservation of traditional art and architecture. The scarcity of traditional materials such as wood and quality mortar, coupled with unskilled labor and high price for construction has damaged or destroyed traditional structures that remain a challenge. This results down in reconstruction of new modern buildings or partially modified buildings. These modified buildings and new buildings have less energy performance than the original traditional buildings. The traditional buildings use passive techniques and materials i.e. use of insulating materials, wall thickness, roof, orientation, etc.

The convergence of post-disaster recovery and sustainable housing practices can have created a new direction in the better energy performance of buildings.

Need

Nepal is very prone to disaster and the climatic conditions vary strongly in Nepal, from hot sub-tropical climate to cold tundra climate. The local climate and building design will define the possibilities of creating a comfortable indoor climate. If the knowledge of energy-efficient building techniques is used, the indoor climate can be, improve and the amount of fuel used for heating or cooling can be reduced. There are many benefits of implementing energy efficiency in post-disaster housing reconstruction like low energy bills, cleaner energy source, clean environment etc. Energy efficiency saves thousands in utility bills while making the environment healthier and more comfortable for occupants. The use of energy efficiency features such as effective insulation, high-performance windows, tight construc­tion, and energy-efficient lighting and heating and cooling systems should be encouraged while designing the model for reconstruction housing.

The first step towards implementing energy efficiency techniques could be to use passive techniques and climatic design when building modern architecture. Most of the houses and settlements that are affected by the earthquakes need restoration or new provisions of energy system for meeting their lighting and cooking energy needs. Access to efficient lighting and clean cooking solutions will be the most important factors in the new housing and human settlements. Solar is used for direct heating and drying purposes and for generation of electricity. Solar energy is an abundantly available clean energy source in Nepal that can use widely in both rural and urban areas. Solar Photovoltaic can also become an effective means for backup energy in case of emergency. The building envelope, passive heating, and passive cooling technique should be followed for energy efficient building.

The wastes from the household after the disaster have become the major factors that contribute to degrading the environment. Hence, their proper management at the household level can be the remarkable step to minimize the pollution ultimately leading to environmental sustainability. During the post-earthquake reconstruction, the planners should consider a people-friendly planning where the people from affected areas would involve themselves. The planning should be such that the needs of people and environment could balance so that there was cooperation rather than competition between them. Building energy efficiency contributes significantly to sustainability by decreasing the environmental impact of energy use. While achieving energy efficiency is an important feature of the sustainable design, selecting construction materials with minimal detrimental environmental effects presents an equally important challenge. The most desirable building materials would be those, which were locally available, made from renewable resources, easily handled with local skills, thermal mass, or insulation, and used little energy to produce, transport, and install. There can be a shortage of water during a disaster so; rainwater-harvesting techniques should be implemented. Rainwater harvesting system helps in storing water that can use at the time of need. Therefore, implementation of energy performance is need during post-disaster housing reconstruction.

Importance

Nepal situated in the cold climatic region. The climatic analysis revealed that passive heating is required in winter months. Semi-compact planning should be done in this region so that maximum solar gain can be obtained to heat the building and air movement is also adequate within and around the building. The building should be located towards the northern side of the site such that the southern face gets maximum sun radiation without any obstruction to sun movement. The buildings in this region need to be south oriented with east-west elongation, to receive lower angle sun in winter.

Vernacular architecture is the result of hundreds of years of optimization to provide a comfortable shelter in a local climate using available materials and known construction technologies. Due to the absence of mechanical means, traditional buildings use solar passive measures to achieve thermal comfort conditions. In most developing countries, it can observe that with the modernization of the building sector this traditional knowledge of smart and climate responsive design is being lost. Indigenous material and vernacular architecture performance, (Bodacha 2014).

The current trend of construction building has changed. The material like concrete and CGI roof will affect the thermal comfort inside the building. The locals prefer to use the concrete rather than indigenous materials. Feasibility of imported material is not checked due to lack of proper information. Without Planning of energy consumption, local copy the modern technology for reconstruction of their building.

The proper guideline of vernacular architecture building must provide. The Climatic responsive building can build with local building material. The people shift toward the modern trend of construction. That will cause future high-energy demand. So, it affects sustainable socio-economic development. The thin layer of brick masonry with cement mortar cannot perform well than traditional local thick brick masonry with mud mortar.

Problem

After the massive loss of life and property, millions of people started camping out in open. They lived in complete fear of forthcoming aftershocks and the fear of the existence and survival in future. More than a month of disaster, people still lived in either temporary or provisional shelters in spaces to be safe from the natural calamities. This put a tremendous demand on the government to supply essentials for the victims.

The disaster not only affected the life and property but also it affected their social life of the victims. After new construction of temporary houses, it did provide shelter but it changed daily life pattern of people. The provision of similar prototype low-cost housing is designed by government and provided to victims. The new construction housing included new building materials, building techniques that were different from the traditional houses. Even after the shelter was provided, they believed their social life was disturbed, as the traditional houses reflected the ethnic group of people, their social lifestyle. Houses of the different religious group differ in different ways, like the house planning, design, facades, building materials, etc. These traditional houses are constructed with locally available material that provided better insulation. The kitchen position and planning is to rely on their cultural aspect and their cooking techniques reflected their heritage. By the changes in shelter, the concrete constructed had lesser insulation in order to protect from harsh outdoor climatic conditions that hampered the indoor comfort level. The traditional houses were like a heritage to them as their ancestor has used their skills and ideas to build them. They had emotionally attached to their house, it not only provides shelter but also a learning from there ancestor. Due to this, they fear that these skills, learning of their culture, religion, and heritage is going to be disappeared and their children cannot learn any of it. The reconstruction may provide shelter, but it can give rise to long-term issues regarding family values, culture, tradition, indoor thermal comfort.