Minimum information modelling rules (BIM Basic IDS)
Basic specifications for delivering BIM information, version 2 — a concise set of openBIM rules so that different collaborators' IFC models 'speak the same language'. Adapted by buildingSMART Romania from the digiGO original.
Minimum rules for IFC models that "speak the same language"
BIM Basic IDS is a concise set of basic rules for delivering BIM information. The goal: that individual models produced by different designers, in different software, become interchangeable and interpretable when exchanged in the open IFC format. It is the simplest starting point for openBIM collaboration — a common minimum any team can adopt immediately, at no cost.
Why we exchange information
The purpose of an unambiguous exchange is the efficient and effective (re)use of information about a construction, throughout its entire life cycle.
How we exchange information
With the help of the open IFC data standard, information is exchanged independently of software — no matter which program each collaborator uses.
What we agree on to enable collaboration
How the structure of individual models is set up so that different models become interchangeable and interpretable.
File naming
Uniform, consistent naming of the individual models within a project.
<...>_<...>_<...>.ifcLocal referencing
Coordinates the positioning of individual models relative to each other, respecting the common origin point.
0.0.0 · x y zBuilding storeys
A consistent naming convention; assigns each object to the correct storey of the building.
IfcBuildingStoreyCorrect use of entities
Use the most appropriate entity for the object and complete it with a type enumeration, where possible.
IfcEntity.EnumerationStructure and naming
Assign the Name and Type properties consistently. Their combination makes clear what the object represents.
IfcName + IfcTypeClassification system
Assign each object a classification code of at least four characters, per the latest version in the respective country.
Code ≥ 4 charactersProperty sets
When transferring properties, use the PropertySets prescribed by buildingSMART in the international standard, wherever possible.
Pset_EntityCommonDuplicates and intersections
Duplication within an individual model is not allowed; in principle, neither are object intersections.
No duplicatesWhat information is required as a minimum
Agree together on what information each party provides and when. Start with the topics below and expand them if needed.
Spaces
Bounded volumes and areas with a function in the construction. Create IfcSpace and name the function; group into zones with IfcZone.
IfcSpace / IfcZoneBuilding service systems
Group the building-services objects that belong to the same system, where applicable.
IfcSystemLoad-bearing / non-load-bearing
For objects, indicate where relevant whether the LoadBearing property is TRUE or FALSE.
LoadBearingInternal / external
For objects, indicate where relevant whether the IsExternal property is TRUE or FALSE.
IsExternalFire safety
Use FireRating (resistance to fire penetration and spread) and FireRatingR (fire resistance), where relevant.
FireRatingPhysical properties
Embed the relevant building-physics properties in the objects.
Physics PsetMaterial
Assign a material (IfcMaterial) to all objects. In assemblies, choose the dominant material.
IfcMaterialProject-specific information
Determine the specific information required for the intended BIM applications and the project objectives.
Project-specificThe complete infographic
All 16 rules on two A4 pages, ready to print and post for your team.
📄BIM Basic IDS — A4 infographic (RO, 2024)
Basic specifications for delivering BIM information, version 2. A4 format, 2 pages.
Download PDF →Licensed under Creative Commons BY-ND 4.0 by digiGO. Romanian-language adaptation by buildingSMART Romania.
Start openBIM collaboration with a common minimum
These rules are made available for free by buildingSMART Romania to support the adoption of openBIM and the IFC standard in your projects. Adopt them as a starting point and expand them as needed.