What is an IFC Schema Version?
The most common version of IFC is 2×3. It was submitted to ISO and published in 2008 by ISO as ISO/PAS 16739:2005. While this version has the most widespread support amongst BIM and AEC software its feature set is limited due to its age.
IFC4, which was released in 2013, came with several extensions in building, building service and structural areas, enhancements of geometry and other resource components, along with numerous quality improvements. These improvements facilitate in conducting better analytics of building information.
The latest stable release of IFC is 220.127.116.11. Please refer IFC Schema Specifications – buildingSMART Technical for more information.
IFC 4.3 is currently a release candidate, and supports new element types used in the infrastructure industry, such as railways and bridges.
Why is IFC Schema important?
IFC2x3 and IFC4 are not fully compatible with each other. BIM Data is represented differently in the 2 versions. It is, therefore, a common practice with OpenBIM projects to agree on the IFC version to be used beforehand.
On the bimspot platform, the properties of all building elements can be easily looked up and filters can be added to create KPIs and QTOs. These features rely on a common data set or a common IFC schema.
Once a project is set to a specific IFC version, the schema of that IFC will be used for all aggregations, analytics and business logics. If filters, KPIs and QTOs have already been set for a project, a new upload with a different IFC version would cause these features to break. It will also disrupt the consistency of the data in the project. To prevent this issue, regular checks will be conducted when processing incoming files, and the issues that are found will be communicated clearly to the uploader through emails.
What does it mean for your project?
Once 1 IFC Schema is in use in a project on bimspot, you have 2 possibilities:
1. You can upgrade to a new version
It is possible to upgrade the IFC version of the project. However, filters, KPIs and QTOs might have to be adjusted to use the properties of the new schema.
If your software allows, it is recommended that you use the latest stable version of IFC when exporting your models.
2. You can’t downgrade to older versions
While all information in IFC2x3 are available in newer versions, IFC4 is not backwards-compatible. In several cases, the same filter or KPI cannot be made using an older version of the schema, simply because the data does not exist there.
For instance materials, element subtypes such as drywalls or glass walls, and so forth are not available in IFC2x3.
So, in case you need a downgrade, please contact us.