31 July 2023
by

The NBS BIM Object Standard 

Originally launched in 2014, the NBS BIM Object Standard has been kept up to date for current BIM processes. It defines requirements for the information, geometry, behaviour and presentation of BIM objects – the digital building blocks of modelling – and enables greater collaboration across the construction industry. It is a quality standard for BIM objects, and a benchmark against which objects can be consistently assessed.

The Standard provides reassurance of quality levels across objects, and consistency across multiple authors in a team. It enables the comparison and analysis of BIM objects that meet the Standard – irrespective of where the object was created. This supports quick and informed decision-making, and allows all objects to be brought in line with the target quality.  

The Standard is intended to assist construction professionals, manufacturers and other BIM content developers in creating BIM objects that operate in a CDE (common data environment), and in line with international BIM processes. 

The Standard is not intended to specify how to create BIM objects in specific software platforms. It is assumed that users of the Standard will have the requisite knowledge to apply it to their software of choice. Through the use of a common standard, the integration of information management and the effective use of object data become possible. 

 

Why is it important to create BIM objects to a standard? 

In 2014, the lack of an industry-wide agreement on the requirements for BIM objects was holding back adoption of information management processes. This resulted in lost data and wasted time – particularly during exchange of model development at the end of project stages. It was also clear that product data and manufacturer objects varied in quality. NBS therefore worked with industry to set out the minimum levels of data properties, geometry, object behaviour and visual appearance that resulted in a high-quality BIM object, and encouraged consistency in authoring between professional creators.  

The NBS BIM Object Standard established the minimum requirements for BIM objects, and also advanced interoperability between BIM technicians and designers. It was essential that the Standard was vendor-neutral and didn’t propose that one platform was superior to another. It couldn’t require that objects behave differently in specific software tools, or that they had to be generated by NBS or a specific manufacturer. Development of the Standard involved engagement with industry professionals and leading software vendors Autodesk, Bentley, Graphisoft, Nemetschek and buildingSMART UK to determine interoperability. For example, the NBS BIM Object Standard details clear information requirements around utilizing international standards like IFC and COBie. This ensures that when data is exported from proprietary design tools that the correct property names and permitted values are included in these respective property sets.  

With standardized information between objects, comparisons between properties and performance become easier. This is a key benefit of NBS Source functionality, allowing the user to select an appropriate product for the project and standardizing schedules – aligning the same properties across model information. Objects that use the NBS BIM Object Standard as their foundation will be easy to source, use, compare and exchange between clients, designers and manufacturers.  

These guiding principles are the foundation for robust objects, so they always contain the relevant properties and data required for use in project models, and required for future asset management. Objects authored to the Standard will perform consistently in the user’s BIM platforms. They contain a consistent amount of visual detail and data properties, resulting in an intuitive and reliable experience. This consistent kit of parts becomes a standard approach to creating digital buildings and virtual assets, with the whole project life cycle in mind.  

In the long term, robust objects allow project data to be compared across portfolios of built assets to:  

  • achieve greater whole life value;  
  • influence future project decisions; and  
  • open up data optimization to learn what worked well and what can be improved.  

 

What are the sections of the NBS BIM Object Standard? 

Requirements in the NBS BIM Object Standard are detailed in five sections: ‘General requirements’, ‘Information requirements’, ‘Geometry requirements’, ‘Functional requirements’ and ‘Metadata requirements’. 

General requirements

These general requirements apply to all BIM objects and cover general data. The scope of this section includes requirements such as object categorization, IFC element type and predefined type requirements. 

Information requirements 

This section defines specific requirements for the information contained within BIM objects. This includes requirements such as property sets, values, as well as COBie and IFC properties. 

Geometry requirements 

The geometry section defines the minimum geometry properties of BIM objects, which describe the physical form of the construction product. A number of factors affect how detailed the object geometry is, such as the type of BIM object and how it is intended to be used, together with the practicalities of working within BIM platforms to arrive at a common approach. The scope of this section includes geometric detail, dimensions and measurement requirements.  

Geometric requirements are divided into: 

  • General geometry data. 
  • Shape data. 
  • Symbolic data. 
  • Surface/ material data. 
  • Connection data. 

Functional requirements 

This section describes the functional requirements that should be embedded within the BIM object – to represent behavioural characteristics like object constraints and their connectivity to other parts of the model. 

Metadata requirements 

This section defines metadata requirements for BIM objects, for the management of the object among other BIM data. The scope of this section includes: naming conventions for files, objects and properties; how materials are applied; and associated images. 

Guidance 

Along with the core requirements and standard properties listed in the NBS BIM Object Standard, there are comprehensive guidance, generic examples and definitions. These help users understand and apply the content to their object authoring, internal BIM processes, project work and model development. Two versions of the Standard can be downloaded in PDF format. The simpler version contains just the requirements, and the longer PDF also contains the guidance, examples and definitions. 

Download the NBS BIM Object Standard. 

Related articles 

These related articles on NBS BIM objects, shared parameters and NBS templates will help you with applying the Object Standard to your daily work: