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The construction industry is highly fragmented, and experts need to coordinate and exchange data. Without consistent terminology, achieving true interoperability and automation is difficult.
Publishing MEP results in bSDD also enables other users to reuse the terms from RAVA3Pro, as well as further develop the content.
Beyond IFC
Data exchange usually happens by structuring the data according to the Industry Foundation Classes (IFC) standard. IFC is a data standard that has been implemented by almost every software vendor in our industry. It provides a reliable way to transport data in a standardized structure to other experts. IFC is commonly used to integrate data from multiple experts into a comprehensive model for advanced projects and engineering. Using different rulesets this combined data can then be ‘clashed’ against each other to find areas that need more intense coordination.
Beyond that use-case, which is very common these days, there is an increasing need to understand more details about objects in an IFC dataset. This is needed to get more detailed and advanced rules for coordination, but also for more advanced use-cases like simulations.
The IFC standard has not standardized everything in our industry. It is a global, international standard serving as the foundation of data exchange. Interoperability requires a balance between the amount of consensus that can be reached, the adoption of the standard, and how many specific use-cases can be supported. An international standard that needs large consensus is usually relatively small and generic. This increases broad adoption. For example, the geometry standard used in IFC is very generic and used in many other industries. On the other hand, the one-to-one agreement between just a small number of people can be very effective for specific use-cases that only exist in a niche environment. An agreement on what property to use for the exchange between just a few organizations can be created very fast and be very useful but is only effective those few organizations.
The more generic and broad an agreement is, the more it can be standardized. Very specific and custom agreements remain a niche specification. Somewhere in the middle are the national classification systems (e.g. Swedish CoClass, Dutch NlSfb, or American OmniClass, etc), and the agreements within specific industries (e.g. ETIM, eClass, etc). These are standards within the applicable domain or region.
The IFC standard supports the addition of extra semantics to objects. This is done by adding user-defined properties (and property sets) and classification references.
Example of a Stair definition in IFC, and the ability to add additional classification references and user-defined properties.
This mechanism allows for additional semantic agreements to be added to IFC data that is exchanged.
A stair in IFC is exchanged as an IfcStair, with standardized resources like ‘location’, ‘quanties’ and properties like ‘NumberOfRiser’. It also has links to materials and a type like ‘HalfTurnStair’. This is all part of the extensive agreements of IFC, that have also been ISO standardized.
A stair in the Netherlands is usually also classified as ’24.11’ and in Denmark as ‘L-XSB’. These codes can be added to an IFC dataset as ‘classificationReferences’.
In that way an IfcStair is understood by international software as a stair, including the most common (globally agreed) properties and characteristics and it is understood by local software that knows what to do with the additional ’24.11’ or ‘L-XSB’ codes.
It is highly recommended for publishers of these classification systems and additional properties to publish the relationship to IFC. So the publishers of NlSfb have decided that the 24.11 code is a certain kind of IfcStair or IfcStairFlight and typically has properties ‘isExternal’ and ‘Loadbearing’.
Shared definitions
More and more semantic systems that amend IFC like this are looking for a place to publish their agreements to be accessible to users. This is why buildingSMART has created the bSDD platform for data dictionaries. The bSDD is an online database that can be accessed using a webpage to search the content, or an Application Programming Interface (API) so software tools can programmatically connect to it.
The bSDD is hosting classes (terms) and properties, allowed values, units, translations, relations between those and more. It provides standardised definitions for improving workflows, that guarantee data quality, information consistency and interoperability.
Authors of BIM data use the bSDD for easy and efficient access to all kinds of standards to enrich their models. BIM managers and coordinators use the bSDD to reference in Information Delivery Specifications IDS) and check BIM data for validity. Both user groups benefit from having one entry point to various classification systems, BIM tools and platforms.
Besides national and international classification systems and domain-specific standards, company-specific standards can be stored in bSDD as well.
RAVA3Pro project
In Finland, the RAVA3Pro project has supplemented IFC by defining classification codes on top of standard entities and publishing them on bSDD platform to make easily accessible by users and software. RAVA3Pro project aims to automate the electronic permit process of municipal building control and construction supervision by applying data-driven processes. The project is led by the City of Helsinki, financed by the Finnish Ministries of Finance and Environment, and involves 23 Finnish municipalities.
Publishing the RAVA3Pro results in the bSDD made them immediately available in software tools integrated with bSDD API, without need for further implementations. For users it means they always have the latest version of the standards available in their tools due to the live connection to the bSDD. For content publishers, it lowers the time to market for their agreements, and guarantees that updates are distributed immediately to end-users. No more out of date excel sheets that need to be manually copy-pasted.
The RAVA3Pro data dictionary contains terms related to MEP (Mechanical, Electrical, and Plumbing) system management. The challenge has always been to streamline the complex web of information related to these systems and ensure seamless coordination among all stakeholders. This new data dictionary provides a common language for all project stakeholders and eliminates ambiguity, enabling a seamless flow of information. MEP designers, engineers, contractors, and facility managers can now communicate effortlessly, reducing errors, saving time, and improving the overall quality of their projects.
With bSDD and other openBIM solutions, the RAVA3Pro exemplifies the future of construction project management, setting the stage for smarter, more efficient, and sustainable building practices. Publishing results in bSDD also enables other users to reuse the terms from RAVA3Pro, as well as further develop the content. It is also possible to provide translations of the definitions which opens the door for the RAVA3Pro project to be translated and used way beyond the Finish borders.
Artur Tomczak
bSDD Product Manager at buildingSMART International
Léon van Berlo
Technical Director at buildingSMART International
Picture: Markus Järvenpää, Granlund