The existing residential building stock accounts for a substantial portion of worldwide energy consumption and greenhouse emissions. Improvements to the thermal performance of existing buildings is a vital activity to mitigate climate change, and often has additional benefits in the form of improved comfort, health and well-being for occupants. Despite the extensive body of literature in this area, it remains a difficult task to assess the performance of retrofit packages in occupied residential buildings.

This study presents three cost-optimal calculations. The overall aim is to provide a deeper analysis and to provide additional guidance on how to properly implement the cost-optimality methodology in Member States. Without proper guidance and lessons from exemplary case studies using realistic input data (reflecting the likely future development), there is a risk that the cost-optimal methodology may be implemented at suboptimal levels.

The white paper puts forward recommendations for the coordinated enhancement of policies, codes, and regulations. It lay out a framework for guidance for the Ministry of Housing and Urban Affairs (MoHUA), the Ministry of Health and Family Welfare (MoHFW), and the Review Committees of the Bureau of Indian Standards (BIS) for the National Building Code (NBC), to harmonise their actions for healthy affordable housing in urban areas.