How Urban Form Impacts Housing Affordability

As more of the world becomes urbanized, Cem S. Kayatekin and Lorenzo Uribe Sanmiguel argue that the way we build cities and “urban form” can have a dramatic impact on housing affordability, livability, and economic development.

The authors make a distinction between bottom-up and top-down development. “Today there are extensive discussions of bottom-up development and how it fosters communities and neighbourhood identity, while the lasting imprints of top-down regimes are still clearly visible in contemporary cities around the world.”

The debate over whether bottom-up or top-down systems are more inclusive and fair persists: proponents of bottom-up approaches see value to the organic development of different forms, while supporters of top-down development assert that uniform systems are more efficient.

Using case studies from Barcelona and Madrid, the authors discovered that “our research both confirmed and subverted the presumed theoretical link between urban form and housing stock, and the presumed supremacy of bottom-up over the top-down areas in fostering economic diversity.”

The study found that bottom-up areas did contain more small and affordable housing units, but that this was largely due to smaller plot sizes. “Older bottom-up areas seem to naturally lend themselves to having more small-scale plots. This is likely due to the incremental development of these areas, and the complex land ownership patterns that developed as a result.”

The broader implication for the housing crisis is that encouraging more small-lot development can boost supply and improve affordability. “What our research indicates is that deeper, more structural approaches may be worth considering – approaches that not only address the physical form of the city, but also the ownership patterns that underpin it.”