basement module 3d model

Create only the BASEMENT (UG) module of a modern minimalist single-family house as pure geometry with no text, labels, colors, or materials. Use a rectangular footprint that will be reused exactly by the upper floors. The model must be a fully manifold, watertight, closed STL-printable mesh with outward normals and a clean, solid perimeter (no distortions or corner defects). Outer walls 5 mm thick, inner walls 4–5 mm, floor and ceiling slabs 4 mm thick. No exterior openings at all — no windows, no outside doors. The basement interior layout is as follows: a central corridor around a U-shaped (double-flight, 180° turn) staircase connecting upward to the ground floor. On the top-left: Storage Room 1. Top-right: Storage Room 2. Bottom-left: Wash Room. Bottom-right: Technical Room. The corridor connects all rooms with clearly visible rectangular door cutouts 25–30 mm wide (scaled) between rooms and hallway. No text or labeling anywhere. The staircase must have realistic geometry: two flights of stairs with a 180°