Introduction

Digital transformation of the construction sector demands trustworthy, interoperable, and economically sustainable mechanisms for managing building‑related data and services. The Horizon-Europe project BUILDCHAIN addresses this need by extending the Digital Building Logbook (DBL) with Decentralized Knowledge Graphs (DKGs), Decentralized Oracle Networks (DONs), and token‑enabled business models to support continuous, verifiable, and machine‑actionable building‑lifecycle documentation.

Methods

BUILDCHAIN ecosystem tools and applications operate within a unified architecture supporting discoverability, access control and monetization. Datasets are transformed into Knowledge Assets (KAs), semantically linked with the DKGs, validated within the DONs by using a reputation‑based mechanism, and stored immutably, ensuring that data providers can confidently monetize their assets. Smart contracts, including Service Level Agreements (SLAs), manage access, payments, and service execution, supporting subscription‑based, usage‑based, or hybrid pricing. A tokenized economic layer enables seamless transactions, access control, automated regulatory compliance and verifiable ownership of digital assets. Economic sustainability is evaluated through multi-actor Business Model Canvases and Value Network mapping, identifying the cost structures and value propositions of urban economy chain stakeholders, demonstrating a win–win sustainable ecosystem.

Results

Three interconnected markets are suppoprted: a service marketplace for BUILDCHAIN tools, a data marketplace for monetizing building‑related datasets, and a side market enabling third‑party applications to integrate with the DBL, DONs, and Building Information Modeling (BIM) ecosystem. Digital wallets and token‑based remuneration streamline partner compensation, enabling transparent, traceable economic flows. The architecture’s viability is shown through a representative scenario where a building‑energy‑efficiency tool uses DBL data and DON weather feeds to optimize HVAC operation. Results demonstrate stakeholder benefits and building‑stock improvements that, when scaled, allow buildings to act as flexible grid resources and enhance city‑wide resource‑management efficiency.

Conclusions

BUILDCHAIN introduces a scalable, tokenized, Oracle‑enhanced business model that transforms DBLs from static repositories into dynamic economic infrastructures, enabling new forms of data monetization, service innovation, and cross‑sector value creation in built environments.