In the article "For whom do we densify? Explaining income variation across densification projects in the region of Utrecht, the Netherlands", we delve into the factors distinguishing high-income and low-income housing projects within the context of densification. This question arises from concerns raised by researchers regarding the affordability of densification projects. Unlike greenfield developments, densification projects are considerably more complex and time-consuming. Developers must navigate strict environmental regulations while considering the interests of neighbouring landowners and residents. Given these barriers, densification typically occurs when it proves highly profitable, often entailing the demolition of affordable housing units to construct market-rate alternatives, thereby displacing lower-income residents. Researchers have voiced concerns that, despite increasing housing supply, the destruction of affordable housing during the process may lead to a net negative effect on housing affordability. Consequently, it is argued that simply allowing for the construction of more market-rate housing is not enough and that densification also has to create housing for lower-income households.

Our examination of all new housing developments over the past decade reveals that, on average, residents in densification projects have higher incomes compared to their neighbours. Nonetheless, there is significant variation. Household incomes tend to be higher in central locations or when densification takes place in well-off neighbourhoods. But, through subdivision of housing or redevelopments by non-profit housing providers, housing for low-income households was created even in central locations. Municipal landownership seems to be powerful in creating affordable housing even in attractive locations, but it is not a panacea. External factors, such as the global financial crisis of 2007 and 2008, compelled public landowners to reduce the proportion of affordable housing in their projects. Moreover, municipalities became more cautious in land acquisition and development post-crisis. In addition, the Dutch non-profit housing sector is under considerable pressure and, in many cases, relies on municipalities for new development land or is forced to redevelop existing blocks. In conclusion, our article underscores that a large variety of outcomes is possible and emphasises the importance of combining densification policies with strategies to ensure affordable housing.