IFC+SG Data Structure
Source: CORENET X — IFC+SG Data Structure ↗ Retrieved 2026-07-10. Content includes full transcription of the page's three discipline infographics (image URLs noted per section).
Core concepts
IFC+SG data is not a single top-down hierarchy: - Spatial structure organises the model (where elements belong). - Property sets store information attached to IFC objects (what data they carry).
Spatial structure (containment chain)
| Level | IFC Entity | Meaning |
|---|---|---|
| 1 | IfcProject |
Overall project container |
| 2 | IfcSite |
Development site or project site |
| 3 | IfcBuilding |
Building, block, or building grouping |
| 4 | IfcBuildingStorey |
Level or storey where elements are placed |
| 5 | IfcSpace |
Room, unit, or defined spatial area |
For CORENET X submission, certain information must be attached at specific spatial structure levels — see the IFC+SG Block Mechanism in general_modelling_practices.md.
Property sets: Pset vs SGPset
| Pset (standard IFC) | SGPset (IFC+SG) | |
|---|---|---|
| Scope | Standard IFC property sets, used across IFC workflows | Singapore-specific property sets for CORENET X submission |
| Content | Common model information | Regulatory information required in IFC+SG |
| Examples | Pset_WallCommon, Pset_DoorCommon, Pset_SpaceCommon |
SGPset_Wall, SGPset_Door, SGPset_Space |
Worked example — Architecture: Door (IfcDoor)
Image: datastructurearchitecture.png — "IFC+SG Data Architecture Element: Door".
4-step chain: IFC Entity → IFC SubType → Property Sets → Properties & values.
- IFC Entity identifies the model object category: Door →
IfcDoor. - IFC SubType / ObjectType (where required): predefined
DOOR,GATE; userdefined (marked*):*BLASTDOOR,*ROLLERSHUTTER. - Property sets:
Pset_DoorCommon(IFC standard, common door properties) +SGPset_Door(Singapore-specific, door data submission). - Properties & example values:
Pset_DoorCommon: FireExit = TRUE · FireRating = 2
SGPset_Door (14 properties):
| # | Property | Example |
|---|---|---|
| 1 | ClearWidth | 1200 mm |
| 2 | ClearHeight | 2100 mm |
| 3 | FireAccessOpening | TRUE |
| 4 | MainEntrance | TRUE |
| 5 | Material | Timber |
| 6 | OneWayLockingDevice | FALSE |
| 7 | OperationType | DOUBLE_DOOR_SINGLE_SWING |
| 8 | OverallWidth | 1400 mm |
| 9 | PowerOperated | FALSE |
| 10 | SelfClosing | TRUE |
| 11 | StructuralHeight | 2100 mm |
| 12 | StructuralWidth | 1400 mm |
| 13 | Thickness | 45 mm |
| 14 | VisionPanel | TRUE |
Worked example — Structural: Beam (IfcBeam)
Image: datastructurestructural.png — "IFC+SG Data Structure: Structural Element".
- IFC Entity: Beam →
IfcBeam. - IFC SubType: N.A. — this element does not use IFC SubType/Type.
- Property set:
SGPset_Beamonly — structural beams do not use standard IFC Psets in IFC+SG. - Properties (25 from SGPset_Beam):
| # | Property | Example | # | Property | Example |
|---|---|---|---|---|---|
| 1 | BeamSpanType | Single | 14 | ReferTo2DDetail | B1-001 |
| 2 | BottomLeft | 3H25 | 15 | ReinforcementSteelGrade | 500B |
| 3 | BottomMiddle | 3H32+3H25+3H20 | 16 | RightConnectionDetail | Detail 1 |
| 4 | BottomRight | 3H25 | 17 | RightConnectionType | Pinned |
| 5 | ConstructionMethod | CIS | 18 | SectionFabricationMethod | Hot rolled |
| 6 | Depth | 600 | 19 | SideBar | H13-250 |
| 7 | LeftConnectionDetail | Detail 1 | 20 | StirrupsLeft | 4H13-300 |
| 8 | LeftConnectionType | Pinned | 21 | StirrupsMiddle | 4H13-300 |
| 9 | Mark | B1 | 22 | StirrupsRight | 4H13-300 |
| 10 | MaterialGrade | C30/37 | 23 | StirrupsTypeLeft | U |
| 11 | MechanicalConnectionType | Telescope beam connector | 24 | StirrupsTypeMiddle | U |
| 12 | MemberSection | RHS600x30x4 | 25 | StirrupsTypeRight | U |
| 13 | PrefabricatedReinforcementCage | TRUE |
Note: the CoP corpus (
str/beam/) lists 30 params for Beam; this infographic shows a 25-row illustrative subset. The corpus remains the checking SSOT.
Worked example — MEP: Tank (IfcTank)
Image: datastructuremep.png — "IFC+SG Data MEP Element: Mechanical Equipment (Tank)".
- IFC Entity: Tank →
IfcTank. - IFC SubType: predefined
STORAGE; userdefined (*):*DETENTIONTANK,*RAINWATERHARVESTINGTANK,*IRRIGATIONTANK,*SPRINKLERTANK,*BALANCINGTANK,*SECTIONAL,*VESSEL,*RECHARGEWELL. - Property sets:
Pset_TankCommon+SGPset_Tank. - Properties & example values:
Pset_TankCommon: NominalCapacity = 100.0 m³ · EffectiveCapacity = 90.0 m³
SGPset_Tank (8): IsPotable = TRUE · Diameter = 4.0 m · Height = 3.5 m ·
Length = 8.0 m · Thickness = 10 mm · Width = 4.0 m · TradeEffluent = FALSE ·
EquipmentType = Water Tank
Cross-discipline pattern (all three infographics)
Every element follows the same 4-step data chain:
IFC Entity → IFC SubType (may be N.A. / predefined / *USERDEFINED) →
Property Sets (Pset and/or SGPset) → Properties + values
- Blue boxes in BCA's diagrams = predefined (IFC standard) subtype values;
orange with
*= userdefined (IFC+SG-specific). - Full property definitions, allowed values and mapping rules: IFC+SG Mapping File (COP Section 4) and the Excel Mapping File (this corpus's source).