In collaboration with Ramboll, BPIE has developed a report for DG Environment that introduces the concept of sufficiency in the building sector and explores its greenhouse gas (GHG) saving potential, as well as other positive benefits. The study analyses existing research and quantifies the impact of real-world sufficiency initiatives implemented across various EU Member States.

While sufficiency measures in the built environment can take many forms, for the latter, this report concentrates on measures that help to preserve existing building stock. It examines five initiatives that employ different mechanisms. In Germany, this includes the “Aus Alt mach 2 und mehr” (Turn One into Two or More) program in Baden-Württemberg, which offers consultations on dividing single-family homes. In Belgium, the “1Toit2Ages” initiative connects people for shared housing arrangements. Poland’s “Empty Space” project focuses on mobilising vacant properties to house homeless individuals. Ireland’s “Parkwest Plaza 12” project repurposes vacant office spaces, while France’s “National Plan to Identify and Address Vacancy” targets identifying and tackling building vacancies.

The quantification demonstrates that maximising the potential of sufficiency measures can lead to significant CO2 savings – but also brings other benefits. Interestingly, most initiatives were not originally motivated by climate goals but by other objectives: In Belgium e.g., the focus was on affordable housing and fostering intergenerational exchange; in France, the priorities included regional revitalisation, creating housing, and minimising land use; in Baden-Württemberg, the goal was to increase housing availability while reducing infrastructure costs associated with new single-family home developments.

This report contributes to quantifying the impact of sufficiency measures, providing a strong evidence base for policymakers to integrate these initiatives into broader climate and social strategies. The results highlight the importance of recognising building sufficiency as a solution for multiple crises and policy goals. To fully unlock the potential of sufficiency, it is essential to position it as a cross-cutting issue that links climate action, resource conservation, housing, and just transition policies. Facilitating dialogue among policymakers across these areas will help maximise the benefits of sufficiency initiatives at all levels of governance.

The European Commission’s original publication of the report can be found at this link.