The changing typology of urban apartment buildings in Aurinkolahti

This case study examines changes in apartment building layouts in the Aurinkolahti neighbourhood of metropolitan Helsinki, Finland, against the backdrop of rapid urban growth and shrinking apartment sizes. The typological analysis of 99 apartment buildings constructed between 2000 and 2023 identifies three phases of development in morphology and spatial organisation. Key findings highlight a substantial shift towards greater building depths, building layouts with a growing number of units, and increasing typological complexity, resulting in more single-aspect and narrowly spaced apartments. Providing insight into the interplay between typology and housing design quality, the study demonstrates how the conditions for quality have become increasingly difficult with the observed typological shift facilitating urban growth. It raises critical questions about the mechanisms and priorities in housing policy and practices to meet rising housing demand and calls for further research into the drivers shaping these practices. The study stresses the need to reconsider design preconditions at various scales of the built environment to ensure sustainable, high-quality living spaces in rapidly growing urban areas. PRACTICE RELEVANCE The Aurinkolahti case study illustrates how building characteristics such as typology, layout and building depth influence key aspects of housing design, including natural light, adequate space and usability. By tracing temporal changes in typology and related housing design quality characteristics within the apartment building stock of an urbanising neighbourhood, this study provides a starting point for architects and planners for the study and utilisation of best-practice solutions from the existing building stock. In the case study, medium-density block structure, a low number of units for each stairwell, and moderate building depth provide the best preconditions for housing design quality.