Abstract: Converting vacant offices into houses is gaining traction as a meansof addressing housing affordability in Canadian downtowns. Weargue that this adaptive reuse practice is a form of ‘urban retrofit’with the dual potential to tackle affordability and precipitate widerclimate benefits by avoiding carbon-intensive teardown and sup-porting the creation of mixed-use, walkable neighbourhoods instruggling downtowns. Sharing reflections from a Canada–UKstudy tour that visited Halifax, NS, the article traces the planninginnovations and property trends shaping conversion and highlightsthe challenges associated with adaptive reuse practice elsewhere,before identifying lessons for future practice.