Introduction to Climate Change Course Coordinator – Dr. Minal Pathak
Building Construction &
Climate Change (An Indian Perspective) Bhanu Mahajan Sustainable Development and Climate Change CEPT University, Kasturbhai Lalbhai Campus, University Road, Navrangpura, Ahmedabad – 380009, Gujrat (INDIA) e-mail : ar.bhanumahajan@gmail.com Submitted: 13th dec. 2012
ABSTRACT Most experts agree that over the next few decades, the world will undergo potentially dangerous changes in climate, which will have a significant impact on almost every aspect of our environment, economies and societies., and also, the built environment. It is widely known that buildings construction contribute to Climate change. But the main issue is that, how are we going to deal with the direct and indirect impacts of changes in climate on building and construction technology. This paper examines how climate change will effect buildings construction and vice-versa, while showing the linkages and, suggests adaptive and mitigation strategies for building construction.
INTRODUCTION Today, it is widely accepted that human activities are contributing to climate change. The buildings contribute as much as one third of total global greenhouse gas emissions, primarily through the use of fossil fuels during their operational phase1. This paper examines the impacts of building construction sector on climate and similarly, impacts of climate change on building construction, in indian context, while highlighting the main
components of it, and suggest adaptive and mitigation measures.
IMPACTS OF BUILDING CONSTRUCTION ON CLIMATE CHANGE • The cement sector alone accounts for 5% of global man-made CO2 emissions2. • Highest impact is the mining/manufacture of materials and chemicals. • Transport of heavy materials such as
1 Intergovernmental Panel on Climate Change (2007) 2 Climate Change and the Construction Sector: Claudia Kruse, ISIS Asset Management, June 2004
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cement, sand is energy-intensive, • The chemical processes and use of fuel/electricity account for the major portion of the sector’s CO2 emissions. • On-site construction of buildings is relatively low-impact, mainly energy use; influenced by choice of building materials, construction techniques, and distances of transportation. Climate Change Evidence Global Warming Sea Level Rise Melting of Himalayan Glaciers
use of mechanical and prefabricated construction technology, neglecting the vernacular construction techniques, which were labour intensive, and at the same time, efficient in cost and energy. The risen value of real estate, people want to finish the construction process as early as possible, which urges them to use prefabricated and mechanical technologies.
Direct Impact
Impacts on Building Construction
Temperature Rise Loss of coastal land Loss of water sources
Increased energy load and more requirement of cooling devices Increased trend towards more energy intensive higher rise buildings Reduction in water intensive construction activities
Table 1: The direct and indirect impacts of climate change on building construction MAIN COMPONENTS IN CONSTRUCTION: 1. Building material 2. Machinery/ Technology 3. Manpower
BUILDING
1. Building Material: Being the most important component of any building project, climate change will effect the availability and construction of building materials, directly and indirectly. For example, the cost of brick, which has risen threefold in past 10 years, will continue to rise as the government has started putting regulations on stone and sand mining. The cement, also the culprit here, and highly energy intensive material, will cost more as the green building councils and regulatory bodies all over the world are looking for a energy efficient alternate for cement. 2. Machinery: With the local labour getting costlier every year, people are opting for more
use of mechanical and prefabricated construction technology, neglecting the vernacular construction techniques, which were labour intensive, and at the same time, efficient in cost and energy. The risen value of real estate, people want to finish the construction process as early as possible, which urges them to use prefabricated and mechanical technologies. 3. Manpower: Labour have been very cheap in India, as compared to western world. This is one of the major reasons of various infrastructure companies investing in India. So let’s see what are the probable or obvious reasons for the labour being cheap. Firstly, high birth rate, post- independence, specially in the rural areas where most of people are poor. In short, economies of scale , in population. Secondly, most of the labour in cities come
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from rural areas, which are under-developed. Decline in crop yield or lack of livelihood options force them to migrate to cities and work as construction workers. But those working hard in construction of someone’s house or building are unable to construct a house for their own and high cost of living in the cities force them to live in un-hygienic conditions and add to urban slum population. Thirdly, Indian construction industry enjoys the benefit of lack of health and safety regulations for construction workers. Most of the contractors hardly care for the safety equipment required for the worker’s safety , or even the health or conditions of working,
which makes them vulnerable to accidents during construction. Over 48 construction workers have died, and another 98 suffered serious injuries, in a series of mishaps at construction sites during 2008-09 in delhi1. With changing climate, the cities will strive for even basic necessities of living, like water, and making living more difficult. Parallel to this, govt. is realizing the importance of rural development and encouraging it through various schemes and funds. After the launch of the employment scheme like NREGA, we have seen the labour migrating back to the villages, which will make construction in the cities, costlier.
STRATEGIES MITIGATION
mortar or glass concrete usage. There is a possibility of new materials being introduced in the market, which may change the conventional systems. Vernacular and earth architecture also help in mitigation of green house gases.
FOR
ADAPTATION
&
1. Adaptation: Green buildings can be considered as both adaptive and mitigation strategy. For adaptation, they help reduce the energy demand of household. The construction by the use of waste material like flyash is another strategy. It reduces the raw material demand and recycles waste, also it is cost effective. Building construction technologies like Hollow Core block Construction, Filler Slab can be used, which are cost and material effective, and also labour intensive. 2. Mitigation: As earlier mentioned, green buildings also act as mitigation strategy, as it uses alternate materials and construction technology which use less energy, hence reducing their carbon footprint. Use of materials like cement, and glass, which are most commonly used in the buildings, are also highly energy intensive,. So there is a need to find an alternate to the conventional brick.
CONCLUSION We know that there exists a relation between the climate change and construction, which, in Indian context, is not just associated with machines and materials, but mostly with huge manpower, and their livelihoods. There is an urgent need to improve our construction systems if we want to adapt ourselves with the changing climate, and this is only possible when we utilize our strength, that is, manpower. Off course a right combination with technology will always be better.
1 CWG-Citizens for Workers, Women and Children : Infochange 12.12.12
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REFERENCES 1. CWG-Citizens for Workers, Women and Children : Infochange 12.12.12 2. IPCC (Intergovernmental Panel on Climate Change), 2007. Climate Change 2007: Mitigation. Contribution of Working Group III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. [Metz, B., O.R. Davidson, P.R. Bosch, R. Dve, L.A. Myer (eds)], Cambridge, U.K. and New York, NY, U.S.A., Cambridge University Press, 2007. 3. Kruse Claudia (2004), Climate Change and the Construction Sector, ISIS Asset Management: June 2004 4. Laul Anil, Anangpur Building Centre (www.anangpur.org), 2010-2012
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