Given the substantial growth in new construction in economies in transition and the inefficiencies of existing building stock worldwide, if nothing is done, GHG emissions from buildings will more than double in the next 20 years. Therefore, if global targets for GHG emissions reduction are to be met, it is essential that mitigation of GHG emissions from buildings must be on every national climate change strategy. Tackling the emissions problem from the building sector, for example through green social housing, can create jobs, save money and most importantly, shape a built environment that has a net positive environmental influence. Investing in achieving such results in the social housing sector has the potential to boost the local economy and improve living conditions, particularly for low-income communities.

This publication represents another addition to UN-Habitat's work on Green and Sustainable Housing and was produced in collaboration with UNEP's Sustainable Buildings & Climate Initiative (SBCI).

Decision makers in local government face the ongoing challenge of how to provide services to the residents with limited resources. Whether drilling a new well to provide drinking water, renewing a road surface, buying new buses or issuing driving licences, municipal services require resources.

Next to skilled human resources, municipal services also require financial and natural resources. New trucks cost clean air in that their operation burns oxygen, emits carbon dioxide, creates dust, and has negative impact on human health. A new road costs biodiversity in that green space is converted into asphalt and natural habitats are split and separated. At the same time, a new road produces noise, i.e. it costs tranquillity. Similarly, new housing areas impose costs in terms of biodiversity, clean air, agricultural soil, and fresh water since the additional inhabitants will convert more fresh water into sewage. Clearly, municipal action always has both financial and natural cost implications.