BIM Explained

With BIM compliance becoming more and more important, bringing with it a huge amount of technical terms and keywords, it is no wonder that most people in the construction industry are a little confused by it all. With that in mind, we have taken it upon ourselves to produce a glossary of essential BIM terms to know – and here is the final part of it:


Level of Detail

This is defined in PAS 1192-2 as the ‘collective term used for and including the level of model detail’ and the level of information detail as well. It covers the description of the graphical content on BIM models at each of the levels as required by the CIC scope of services. There are three levels and they are: schematic, concept and defined.

Level of Information

This is the description of non-graphical content required in BIM modelling and determines how much detail is needed for things like spatial performance and workmanship.

Life Cycle Assessment

This is a cradle-to-grave analysis of the environmental impact of the built assets, regarding energy and materials. The materials and energy used over the whole life cycle are quantified, along with any pollutants or waste produced as a consequence of a construction activity. The result of this quantification will represent the environmental load of that particular asset. The methodology needed to calculate this quantity is given in ISO14040.

Open BIM

This is an initiative of several 3D Bim software companies using the buildingSMART data model. It is an open-source approach to help companies use a more collaborative design process, including the realisation and operation of the final building. It incorporates data to ISO 16739, terms to ISO 12006-3 and process to ISO 29481-1.

PAS 1192

This is the framework used to ensure that all BIM models adhere to the level of model detail required, the non-graphical information required, the model definition and model information exchanges. There are various sub-clauses to PAS1192 including:

  • PAS 1192-2, which deals with the construction phase of BIM modelling, specifying the requirements to reach BIM2 maturity.
  • PAS 1192-3, which deals with the operation phase and focusses on the use and maintenance of the Asset Information Model for the Facilities Management team.
  • PAS1192-4 which covers the best practice for the implementation of COBie.
  • PAS1192-5 covers security of data (and is currently under development).


This is a classification system that is owned by CIC and is in use within the UK. It groups objects into numerical headers so that they can be grouped according to a class which will be applied to them throughout the life of the asset. The classification categories are:

  • Activities which take part in different areas of the building
  • Complexes such as airports or a university campus
  • Elements including ceilings, floors and walls
  • Entities i.e. individual buildings
  • Products such as fixings or sheet materials
  • Spaces aka rooms
  • Systems such as door and window systems

Uniclass is considered to be a more sophisticated classification system than CAWS because it can cater for assets of any scale, it can accommodate infrastructure and civil engineering projects, and it encompasses the entire lifecycle of the built asset.

For more information on how we can help you with BIM compliance in both the UK and the UAE, please call us on 0161 427 0348 (UK) or 971 4 556 1988 (UAE). Alternatively, you can send us an email to or grant.hood@thecadroom(UAE) for a speedy response to any of your enquiries.