1. The Buildings sector of today has an oversized ecological footprint. The buildings sector is the single largest contributor to global greenhouse gas emissions (GHG), with approximately one third of global energy end use taking place within buildings. Furthermore, the construction sector is responsible for more than a third of global resource consumption, including 12 per cent of all fresh water use and significantly contributes to the generation of solid waste, estimated at 40 per cent of the total volume. Therefore, the building sector is central to any attempt to use resources more efficiently.
2. Constructing new green buildings and retrofitting existing energy- and resource intensive buildings stock can achieve significant savings. There are significant opportunities to improve energy-efficiency in buildings, and the sector has the greatest potential, out of those covered in this report, to reduce global GHG emissions. Various projections indicate that investments, ranging from US$ 300 billion to US$ 1 trillion (depending on assumptions used) per year to 2050, can achieve savings of about one-third in energy consumption in buildings worldwide. In addition, these investments can significantly contribute to the reduction in CO2
emissions needed to attain the benchmark 450
ppm concentration of GHGs. Emission reductions through increased energy efficiency in buildings can be achieved at an average abatement cost of -US$ 35 per tonne, reflecting energy cost savings, compared to -US$ 10 per tonne costs in the transport sector or positive abatement costs on the power sector of US$ 20 per tonne.
3. Greening buildings also brings significant health and productivity benefits. Greening buildings can also contribute significantly to health, liveability and productivity improvements. The increased productivity of workers in green buildings can yield savings higher than those achieved from energy-efficiency. In residential buildings in many developing countries, indoor pollution from poorly-combusted solid fuels (e.g. coal or biomass), combined with poor ventilation, are a major cause of serious illness and premature death. Lower respiratory infections such as pneumonia and tuberculosis linked to indoor pollution are estimated to cause about 11 per cent of human deaths globally each year. Women and children tend to be most at risk due to their daily exposure. Improved access to water and basic sanitation are other significant benefits that come with green building programmes.
4. Greening the building sector can lead to an increase in jobs. Investments in improved energy- efficiency in buildings could generate additional employment in developed countries where there is little growth in building stock. It is estimated that every US$ 1 million invested in building efficiency