Digital environmental product declarations (EPDs) are increasingly published in structured digital formats, yet their direct use in building information modelling (BIM) and life cycle assessment (LCA) workflows remains limited because critical semantic content is still under-specified. Recent evidence shows that the most consequential interoperability bottlenecks cluster around narrative functional units, incomplete manufacturing-location data, undated technical standards, and scenario descriptions that still require analyst interpretation before transfer into software tools. This article develops a methodological framework for converting such essential EPD content into machine-interpretable, UID-aware parameter objects. The study follows a design-science workflow consisting of failure-mode extraction, requirement formulation, schema design, constraint-based re-encoding, and a conservative reproducibility audit of representative digital-EPD cases. The proposed framework formalizes each essential exchange object as a quintuple comprising persistent identifier, declared value, unit or controlled class, contextual qualifier, and dated reference standard. It further introduces a granular domain architecture linking organization, family, product, and property/scenario domains, together with operational metrics for parameter determinacy and human mediation burden. Three worked cases — functional-unit declaration, A4 transport scenario, and C4 end-of-life routing — demonstrate how narrative statements can be transformed into structured parameter bundles suitable for reuse in EN ISO 22057, ILCD+EPD, IFC, and digital product passport environments. Across the demonstration set, the framework increases explicit semantic coverage while preserving traceability to the original declaration logic. The paper contributes a reproducible implementation pathway for reducing manual interpretation in BIM-LCA workflows and enabling more reliable use of manufacturer-specific environmental data in sustainability assessment.