The building construction industry is a major contributor of environmental pollution, with high levels of energy consumption and greenhouse gas emissions, all of which contribute to climate change. Housing is the single largest subsector of the construction industry. It is also a basic need associated with social and economic benefits, and its demand in most emerging economies is substantial. Hence it is a sector with significant potential not to mitigate just the negative impact of climate change on buildings and people, but also to reduce the impact of the construction industry on the natural environment. Green buildings technology has advanced greatly in recent years, but most “high performance” green buildings are capital intensive, often with high-tech applications that are not in easy reach of the mass housing market. In the developing country context, where huge segments of the population lack access to essential services or housing, the green buildings approach to addressing climate change is perceived to be largely unaffordable. For green technology to be adopted in poorer nations and have scalable impact, it will have to be low-cost and affordable. According to a 2010 report, buildings in the commercial, office and hospitality sectors are poised to grow at 8% annually over the next 10 years in India. While the retail sector has been growing rapidly at 8% per annum, the residential sector has seen growth of 5% per annum during this period. It is estimated that over 70 million New Urban Housing Units will be required over the next 20 Years.
 Embodied Energy.
 Affordable Housing Energy Efficiency (AHEE), “Affordable Housing Energy Efficiency Handbook,” 2007.