QTO MEMO — Duplex apartment handover (2026-08-25)

The attached space schedule (bom_spaces.csv) was exported straight from the
design tool's 'GSA Space Areas' quantity sets. Those quantities are
export-time snapshots: they were computed by the modelling tool's own area
rules and were never re-validated against the delivered geometry. Do not
trust a quantity set over the geometry it describes — recompute each space
area from the Body representation (the spec sheet defines the area rules
for both SweptSolid and SurfaceModel bodies) and reconcile the schedule
against that.

The model itself is the released IFC2x3 coordination view. The IFC4
handover must be a real schema migration: entities rebuilt with their full
IFC4 attribute sets, the deprecated IfcWallStandardCase class migrated to
IfcWall, and every wall carrying a complete Pset_WallCommon attached to
the wall entity itself. Element identity travels by GlobalId.
