A popular source for CC0 public domain textures that can be imported into Lumion as standard materials. Poly Haven:
While there is no single "official" standalone download for the Lumion 8.5 material library (as it is typically built into the software installer), you can expand your library by downloading high-quality, free PBR (Physically Based Rendering) material packs that are compatible with Lumion 8.5 Recommended Free Material Resources Lumion 8.5 Material Library Free Download
Lumion 8.5 stands as a highly reliable version of the software, known for its speed and striking output. One of the core reasons for its success is its extensive, built-in material library. A popular source for CC0 public domain textures
For licensed users: the official material library is complete, stable, and fast. For unlicensed users: there is no legal “free download” of the full library – using a trial or student version (where available) is the safest route. For licensed users: the official material library is
He downloaded a high-quality "Worn Concrete" pack from a trusted site.