Climate change and the housing sector
Shelter is one of the basic needs of man. As a result, every human being must be sheltered either through self-effort or government effort. Nigeria is currently experiencing a growing urban population and a housing deficit. The growing housing deficit is estimated as ranging from 17-23 million homes. Notwithstanding the need for the establishment of more cities and housing, which is imperative, the challenge is that the impact of constructions and human activities is contributing a great deal to climate change. Nigeria’s Land, Housing and Urban Development Roadmap identified one of the challenges in housing development to be the abuse of the natural environment due to lack of adequate land use planning, resulting in loss of biodiversity, deforestation, desertification, soil erosion and pollution of land, air and water. Also, the demand for energy in the housing sector far outweighs the supply from the national grid. As a result, Nigerians have resorted to generating power privately through the use of generators burning with fossil fuels.
Climate change can be defined as a long-term shift in the climatic pattern of a specific region or planet measured by changes in average climatic elements such as temperature, wind patterns, precipitation. Climate change has negative impacts, which include threat to agriculture and food security, sea level rise, depletion of ecosystems, reduction of tourism potentials, soil erosion, floods and drought and so on. Climate change occurs as a result of production of green house gasese-like carbon dioxide, methane, which traps and retains heat leading to global warming. Part of this heat is produced during energy use.
Recent estimates of the United Nations Environmental Programme (UNEP)’s Sustainable Construction and Building Initiative (SCBI) assigns 30-40% of the global energy use to housing sector. Thus the housing sector is a key source of demand for energy and materials that produce greenhouse gases. Moreover, there are the greenhouse gas emissions from deforestation when vegetation is cleared to make way for houses. According to International Energy Agency data (2015), global residential emissions of carbon dioxide account for about 6% of total global direct carbon dioxide emissions. Of the total 42% carbon dioxide emission from electricity and heat, 11% of it is from residential buildings e.g. use of LPG/gas, oil for cooking, heating and cooling.
Climate change has a lot of impact on the housing sector. High temperatures create heat stress. High temperatures can indirectly contribute to sand dune encroachment in settlements in the Sahel, and can increase the possibility that some settlements will be abandoned. High temperatures speed up deterioration of housing stock and bitumen roads, and increase energy demands through increased use of air conditioning/other cooling systems. Increased rainfall can cause flooding in urban and rural areas, accelerate erosion and cause landslides, and lead to deterioration of roads and other infrastructure. Both extremely low and high rainfall can cause housing deterioration, decreasing the overall quality of housing in settlements. In some cases, changes in rainfall can displace people and communities, creating environmental refugees. Sea-level rise, including storm surge, can cause houses and island communities to disappear, threaten critical public and private infrastructure, and may create the need to rebuild levees, dykes, and other protective measures. Lagos and communities in the Niger Delta are particularly vulnerable.
Meeting the challenge of climate change mitigation will require dramatic advances in technology and a shift in how Nigeria generates and uses energy. Building green is one of the best strategies for meeting the challenge of climate change because the technology to make substantial reductions in energy and carbon dioxide emissions already exists. According to International Energy Agency (2015), the average Leadership in Energy and Environmental Design (LEED)-certified building uses 32% less electricity and saves 350 metric tons of carbon dioxide emissions annually. Modest investments in energy-saving and other climate-friendly technologies can yield buildings and communities that are environmentally responsible, profitable and healthier places to live and work, and contribute to reducing Carbon dioxide emissions.
The Federal Government recently launched the Building Energy Efficiency Guideline (BEEG) 2016, which is an update of the National Building Code of 2006. The guidelines aim to ensure access to sustainable energy service in the housing sector, energy efficiency in building and factors to consider in achieving it. The guidelines are expected to be a handbook for all professionals in the built environment. The guidelines stipulate that to maximize energy efficiency in building, factors to be considered include: the specific micro climatic condition of the site; Site selection, orientation and shape of the building, in line with wind direction; conscious selection of building materials; the use of energy efficient lighting and equipment and deployment of renewable energy in powering few or all the building electrical loads.
• Eke is the Programme Officer, Environment at Centre For Social Justice, Abuja