The heterogeneous impacts of widespread upzoning: Lessons from Auckland, New Zealand

Zoning reform is increasingly recognised as an important strategy to increase housing affordability and environmental sustainability. Few cities have undertaken significant upzoning of low-density neighbourhoods, making the 2016 Auckland Unitary Plan (AUP) probably the most ambitious zoning reform in the world. Parcels zoned for single houses previously dominated Auckland, but three-quarters of them now allow multiple units. Existing studies have documented the building boom that followed this zoning reform, yet the relatively rare case offers additional insights. In this article, we use appraisal, census and zoning data on over 200,000 parcels in Auckland to answer three research questions about the heterogeneous impacts of the AUP. First, to what extent did upzoning increase the appraised value of properties' redevelopment options? Second, did upzoning increase appraised property values to a greater degree in higher-income and more centrally located neighbourhoods? Finally, was zoning reform in Auckland significantly influenced by similar political pressures as in other countries? That is, was upzoning less likely (and downzoning more likely) in higher-income neighbourhoods? The answers to these three questions are substantially, it's complicated, and yes.