Between household structure, urban density, and ecological transition: Rethinking the approach of estimating housing needs in Switzerland

• Estimating housing needs according to demographic scenarios and occupancy targets • Housing stock additional capacity is based on its connection to public transport • Increasing occupancy rate of well-connected housing could avoid new construction • Monitoring vacancy rate could help better define housing strategies • Relevant housing strategies contributes to a low-carbon society Switzerland faces the dual challenge of population growth and carbon neutrality targets by 2050. Against a backdrop of housing and environmental crises, the real estate industry is promoting a sharp increase in the number of new buildings on the one hand. On the other, the idea of a moratorium on new construction is emerging to preserve quality of life and protect the environment. Despite the availability of up-to-date statistical data, figures on vacancy rates, and therefore housing needs, do not reflect the optimal capacity of the current housing stock according to well-connected territories. This work proposes a novel modeling framework based on a prospective and statistical approach to estimate – quantitatively and spatially – housing needs with a view to a low-carbon society. Based on demographic scenarios, occupancy targets, and level of public transport services, it helps determine a more accurate vacancy rate by considering an increased occupancy of the current housing stock. Results show that it could be possible to accommodate a larger part of the population and reducing considerably the CO 2 emissions attributable to the construction of new housing. Finally, we propose a strategy of priority actions to answer housing needs while minimizing the carbon impact of construction and enhance sustainable practices.