The “Building Classification through Geodata Analysis” project was financed by the German Federal Ministry of Economic Affairs and Climate Action (BMWi) under grant number 03ET1315B and ran from 2015 to 2021. Its main objective was to develop a decision‑support system that quantifies carbon‑saving potentials of building renovation and new construction at the municipal level, with a particular focus on the use of timber. The project was carried out in collaboration with the City of Menden, Wood Construction Germany – Institute e.V./Information Society of Wood e.V., the Institute for Housing, Real Estate, Urban and Regional Development (InWIS), and the Information Systems for Raw Materials (INFRO). Five project meetings were held, the first in May 2019 and the last in August 2022, with all meetings from 2020 conducted virtually to maximise participation.
The technical work was organised into four work packages. Work Package 1 produced a calculation tool that estimates carbon storage and substitution potential for timber‑based renovation and new‑build projects. The tool incorporates life‑cycle assessment data from the THG‑Holzbau and HolzImBauDat projects and applies the European standards EN 15978, EN 15804 and EN 16485. It also defines a data interface for geodata collected in Work Package 2 and validates the required input parameters. Work Package 2 developed a GIS‑based specialised information system. A GeoData Warehouse was built with a harmonised data schema, and data were imported using custom adapters and fusion processes. The system was realised as a web‑GIS, with functional specifications refined into technical specifications, user‑interaction mock‑ups, and a continuously updated prototype that utilised real data from Menden. The carbon calculator was integrated into the web‑GIS, providing input forms for user‑defined scenarios and exporting results in widely used formats such as shapefiles (SHP), Excel (XLS) and OGC‑standard services (WMS, WFS).
In Work Package 3 the model was applied to the City of Menden. Building age classes were derived from Level of Detail 2 (LoD2) data, and regional forest, nature reserve and recreational area potentials were mapped. The web application was extended to display additional datasets, including spatial master planning and flood‑hazard information. Scenario calculations explored increased timber use in both renovation and new‑build contexts, yielding estimates of carbon storage and substitution potential. On‑site visits verified the visualisations and informed the abstraction of key features for broader applicability.
Work Package 4 focused on transfer and dissemination. The system was packaged as a web application and made available to the example municipality. Collaboration across all work packages ensured that the methodology could be generalised to other cities, with attention to data structure, quality, and availability at municipal and state levels. Public outreach activities promoted the system’s use beyond the initial partner network.
The project leveraged current norms and tools: it used the updated, norm‑conforming eco‑bau.dat from the Federal Office for Building and Construction (BBSR), public geodata supplied by the Geoinformation Centre of the North Rhine‑Westphalia State Office for Information and Technology, and ESRI ArcGIS Pro for data processing. The GeoData Warehouse supports export to industry‑standard formats and OGC services, facilitating integration into existing governmental geodata infrastructures. The resulting dashboards, maps, and tables provide municipal planners with a robust, data‑driven basis for climate‑friendly building strategies and for promoting timber construction as a carbon‑saving measure.