---

Deep retrofits are widely recognized as critical to achieving Canada’s 2030 and 2050 climate targets, particularly in social and affordable housing, where buildings are often older, less efficient, and home to communities facing multiple vulnerabilities. Yet despite clear policy signals, the literature shows that retrofit progress remains slow, fragmented, and uneven, shaped by misaligned governance, complex program design, workforce and supply‑chain constraints, and limited integration of equity considerations. Understanding how these factors interact is essential to moving beyond incremental change.

As part of the Greener Neighourhoods Pilot Program (GNPP) with funding from Natural Resources Canada ( NRCan), EnviroCentre’s Retrofit Accelerator team undertook this literature review to synthesize existing research, policy analysis, and case studies and to clarify what the evidence tells us about advancing low‑carbon, equitable retrofits at scale. The review connects key conclusions to emerging questions and identifies evidence gaps, highlighting where ambition, implementation, and outcomes remain misaligned. By highlighting both the potential benefits and the conditions required for success, this work aims to support thoughtful planning, collaboration, and long-term impact of deep retrofits in social housing.