In many countries, densification is a central goal of land policies to promote sustainable development. However, while these policies intervene in existing built-up structures and thus affect diverse and complex arrangements of property rights, it remains unclear how they are applied by actors. We argue that an explicit normative point of view is required to better understand this application. To this end, we measure densification in space and interpret the allocation through the lens of justice. Using an automated GIS approach, we analyse the suburban region of Frankfurt, which is covered by a regional land-use plan with ambitious densification goals.