A new deliverable from the LIFE‑funded OBSERVE project sets out the evidence base for establishing national Building Stock Observatories (nBSOs). The document clarifies what these systems must deliver under the evolving EU policy framework and assesses the readiness of Croatia, Cyprus, France, Greece, Italy, and Spain to develop building‑related monitoring structures.

The report evaluates national building‑data ecosystems across nine thematic domains, including building stock, energy performance certificates, renovation activity, HVAC inspections, nearly zero‑energy and zero‑emission buildings, building renovation passports, the smart‑readiness indicator, and energy poverty.

The deliverable concludes with recommendations for phased and modular BSO development, minimum interoperability requirements, and workflow‑based quality‑assurance and governance arrangements. These results will guide upcoming work on dataset architecture, data‑collection processes, and monitoring mechanisms in the pilot Member States.