What information does it provide?
The existing building stock contains significant quantities of building materials. The objective is to utilize these materials for as long as possible, only demolishing, reusing, recycling, or repurposing them at the end of their service life, thereby keeping them within the material cycle. To develop effective strategies and business models for circular construction, detailed information is essential regarding the types and quantities of building materials used, their allocation to building components, and the timeline for their availability. A material cadastre can provide this important information.
Until now, data on the composition and distribution of building materials has been scarce, as the collection of such data is highly time-consuming. However, the National Material Cadastre, developed by the IOER, now offers comprehensive data for every municipality in Germany for 2022.
The National Material Cadastre includes information on building materials for 51.6 million buildings, categorized into 44 distinct building material groups. Additionally, it provides further insights into categories such as grey emissions.
Results
Germany`s building stock comprises approximately 20.8 gigatons of building materials.
Among these materials, concrete dominates with a 46% share, followed by sand-lime brick and conventional brick each account for just under 10%. Renewable building materials represent only approximately 1% of the total according to these calculations.
Regarding grey energy – which quantifies the CO₂-equivalent emissions produced during material manufacturing under current conditions – the greenhouse gas potential stands at approximately 2.86 gigatons CO₂-equivalent. Metals account for 40% of this total, while concrete contributes roughly 22%.
Data foundations
The central data basis of the Material Cadastre Germany comprises the LoD2 data set of the federal government, containing approximately 56 million structures, of which roughly 51.6 million are classified as buildings.
Building-level modeling is implemented utilizing building volume derived from 3D building models, corresponding approximately to gross volume (underground building sections excluded).
A building typology approach facilitates differentiation within the building stock, enabling linkage between typified buildings and corresponding type-specific material indicators.
The typification of the building stock is essentially based on the building functions shown in the LoD2 dataset and a complex geometric filter. This enables a distinction to be made between one/two-family houses, multi-family houses and non-residential buildings.
The results are provided as geodata (GeoPackage) on the level of buildings, administrative units (time status: 2022), and geogrid. When using the data, it should be noted that ––due to the type-based approach–– the information provided on the individual buildings can differ significantly from the materials actually used in the building. Targeted data aggregation of the building-related dataset is essential for a meaningful and appropriate interpretation of the data.