Spatiotemporal evaluation of embodied carbon in urban residential development

The building sector emits over one-third of anthropogenic global greenhouse gas emissions annually. New construction alone threatens to consume the remainder of existing carbon budgets. Therefore, immediate actions are urgently required to mitigate these emissions. The current urban planning paradigm favours densification. However, it remains unclear how densification policies have influenced the embodied carbon emissions (EC) of new residential developments. This study evaluates residential development trends and associated EC across six urban regions in Finland between 2000 and 2021. Quantitative methods are used to compare and assess comprehensive building data with state-of-the-art whole-life carbon data. Although densification in many Finnish urban environments has reduced floor area per capita, it has also increased EC intensity in residential development by 5–10%. Spatial analysis further reveals that higher average emissions intensities occur in areas of high-volume development. These higher EC intensities are attributable to changes in housing construction and a corresponding decline in timber construction. Policy relevance As a significant portion of emissions is already generated before a new building is even in use, future policies must account for the temporal impact of EC from new construction activities. Given their substantial authority over land-use governance, municipalities need policies to reduce the environmental burden of new construction. These policies include assigning carbon limits for all new buildings and mandating quotas for low-carbon construction material use in new zoning plans. Municipalities should also more actively enforce mandates for low-carbon construction before land leases or transfers.