Vera Götze

Affordability is the most salient housing policy issue in the United States. It is also conceptually elusive. The most cited metrics, such as rent burden and rent-to-income ratio, collapse disparate processes into a single outcome, obscuring substantial heterogeneity across people and places. Moreover, these measures are only weakly correlated with rents, meaning that famously expensive metros like San Francisco and San Jose appear just as affordable as Cleveland and Minneapolis. In this article, we assess the analytical value of conventional rental affordability measures by decomposing them into their underlying drivers over time. Using data from 1960 to 2024, we analyze how changes in the renter population, household composition, rents, incomes, and housing supply elasticity across urban areas relate to rental affordability. We focus on rental affordability because most low-income households are renters, and because renters are more vulnerable to eviction and homelessness. Affordability has worsened over the last six decades, primarily because of rent increases. We find that fluctuations in incomes play a large and underappreciated role in changing affordability metrics over shorter time periods. Rents have diverged across metro areas without a corresponding divergence in measured affordability. Housing supply elasticity is more strongly correlated with rents than with rent burdens, suggesting that people adjust to higher rents and lower incomes along multiple non-financial margins. We examine three of these; living with parents, overcrowding, and migration, and find they connect more strongly to rents than to affordability measures. Our findings highlight the importance of multiple measures of housing market problems.

The business of densification refers to more or less aggressive urban development practices that use the broad political consensus on the need for urban densification to promote profit-driven development, often dressed up in the rhetoric of eco-efficiency, and to the detriment of social policy objectives (e.g. affordable housing, cultural heritage, community cohesion). The implementation of urban densification requires deep changes in the practice of land-use planning because, as opposed to greenfield developments, it occurs in a complex web of established rights and interests. These more active forms of planning interventions are referred to as “land policy” in a growing body of literature (including in this special issue). In the context of densification, land policy tends to be appraised in planning debates as purely instrumental, that is, as a more effective and proactive administrative strategy for improved project implementation. In this commentary, relying on empirical data from the Netherlands and Switzerland, we argue that land policy is in fact a hybrid construct that merges both progressive and neoliberal elements. We discuss how the hybrid nature of land policy generates tensions in project implementation as different discourses and representations collide. Therefore, there is a real need to accurately assess the true ideological scope of urban changes implemented in the name of densification, as land policy is fundamentally value-loaded. If planners remain blind to the political dimension of land policy, the business of densification will flourish, and social sustainability objectives will be systematically relegated to the background.

Municipalities develop individual land policies and can choose not to apply available planning instruments or to apply them differently than intended. While this strategic action can endanger the effectiveness of public policies, it is rarely considered in large-scale analyses. A new geospatial method is presented that captures such strategic action. Empirical evidence from the Canton of Bern, Switzerland, reveals municipalities’ application of planned unit development (PUD), an instrument potentially allowing for flexible zoning negotiations to promote densification. Detailed zoning and building data from the period 2002–23 are used to examine the variation in PUD application by municipalities and whether they apply it to enable densification. Distinguishing by municipality type (i.e. urban core, small town, suburban, rural or touristic) reveals that PUD application is connected to projects with higher building density, more complex parcel changes and, for urban and suburban municipalities, higher density gains in low-density neighbourhoods. However, rural municipalities seldom apply PUD. New indicators of planning complexity provide an insight into whether municipalities apply instruments to enable densification under difficult circumstances. Practice relevance Many policy instruments are provided for in the law, but it is unclear whether and how they are used in practice by municipalities. Following urban densification objectives, municipalities often struggle to implement planning or housing policy instruments, which target private landowners and developers. Therefore, evaluating how different municipalities apply policy instruments and how this application contributes to reaching stated policy goals is crucial. Therefore, this research explores new ways to capture the effect of policy instruments with spatial analysis. Furthermore, by examining the real-world implementation of PUDs, this research sheds light on possible barriers to PUD application for densification, thereby helping policymakers and urban planners improve the effectiveness of public policies.

While governments worldwide rely upon compact city policies to reduce land consumption from urban growth, recent studies have addressed the potential trade-off between densification and housing affordability. Concerns have been voiced that densification leads to a one-sided housing supply, structurally excluding low-income households. However, few studies address household income variation across densification projects, leaving us with a limited understanding of the circumstances under which exclusion occurs. To this end, we explore household incomes in densification projects between 2012 and 2020 in the Province of Utrecht, the Netherlands, where urban development is traditionally strongly regulated through active land policy. At the same time, current shifts towards a more deregulated housing market make for an interesting case. Exceptional access to detailed cadastral and census data allows us to identify densification projects and assign them a median household income each. We investigate the influence of location and transformation process on household incomes through regression analysis and conduct qualitative case studies of projects whose median income was highly mispredicted by the regression model. This allows us to integrate non-quantified factors, such as land ownership and public policy interventions, in explaining such interesting cases. For the Province of Utrecht, our study confirms that while households in densification projects earn significantly more than their neighbours, the range of incomes in densification projects is large. Project characteristics such as centrality, neighbourhood status and transformation process explain only a small share of this variance. For cases where median incomes are much lower than predicted by the model, public land ownership, in combination with inclusionary zoning, is essential in ensuring housing affordability. Our approach highlights the necessity of supplementing densification policies with measures that secure affordable housing.

While governments worldwide develop policies to promote urban densification, critics point to possible negative effects of densification on social sustainability. The occurrence and distribution of these negative social effects are strongly influenced by land policies. This makes it crucial to monitor the role of land policies and understand what processes shape urban development in the context of densification. To do so, detailed, large-scale international comparisons of densification patterns, including building and social changes, are needed. We address this issue by introducing a method to measure and compare urban development in two countries with contrasting planning systems: the Netherlands, where public actors play a strong and active role, and Switzerland, where strong private property titles and a highly democratic planning system are prevailing. Our GIS-based method analyses densification processes within their surrounding morphological and socio-demographic context. A k-proto cluster analysis on highly detailed spatial and statistical data based on housing units, covering 2011–2019, results in five densification types. The distribution of these types reveals different patterns in the two city regions of Utrecht (NL) and Bern (CH). Most strikingly, contiguous redevelopments frequently occurred in Utrecht but hardly in Bern, pointing at possible advantages for Dutch municipalities to intervene in property rights. While having developed an empirical basis in this study, future research that refines the analysis of the legal, planning and ownership conditions underlying the identified densification patterns can contribute significantly to policy evaluation.