The material stock needed to reduce disparity in access to basic services: a case study of India, across spatial scales.

The relationship between built environment stocks and living standards is critical to sustainable development. Yet the coupling of environmental impacts and human development outcomes warrants greater consideration. Here, we assess development outcomes associated with built environment services and quantify their relationship to the material composition of such services, across scales, for the first time, using India as a topical testbed. The multiscale model we present reveals that the provision of built environment services remains a challenge within India, with varying heterogeneity across spatial scales of intervention. This highlights the need for assessment across these scales to identify the most suitable intervention points. We show that brick and concrete stocks have grown in conjunction with development outcomes. Building on this, we estimate that upgrading inadequate housing would require between 2.2 and 5.3 Gt of material, which represents approximately 0.5% of the global carbon budget remaining to stay within 1.5° of warming.