Discover 10 terms about BIM and openBIM in construction industry you should know

10 BIM Terms Everyone Should Know


1. BIM – Building Information Modeling

BIM stands for Building Information Modeling. Working methodologies and a 3D parametric digital model that contains intelligent and organized data are the core components of BIM. From design to demolition, BIM is the sharing of accurate information throughout the life of a building or infrastructure. The model is a computerized depiction of a building’s or infrastructure’s physical and functional qualities. BIM is often used as a reference to the actual model (or models), as well. However, the primary definition is focused on the process.

BIM is sometimes thought of as software or technology. That is not accurate. It is more accurately processes or workflows that are followed throughout the design, construction, and use of a structure. BIM, is an inclusive environment facilitating  the contributions of the entire project team. 

Learn more about BIM here.


2. BEP – BIM Execution Plan

The BIM Execution Plan (BEP) is a crucial document for a  project’s effective BIM implementation. BEP includes the organization and graphical representation methods for the operation, the processes, models, and uses, according to the project’s specificities (i.e., rehabilitation, new, allotment, etc.). The BIM Execution Plan also establishes the responsibilities and accountability of team members, and the technologies that will be utilized on the project. In short, it describes the expectations for BIM use according to the project’s specifications

Learn more about BEP here.

Learn more about the benefits of BEP here.


3. CDE – Common Data Environment 

A CDE collects all of the project’s shared data and makes it available to all of the participants. The formation of a CDE is a requirement for implementing BIM on a project.

Learn more about CDE here.


4. IFC – Industry Foundation Classes 

IFC is an open BIM data interchange standard. It can be compared to a BIM PDF. IFC files are a frozen representation of the original material, similar to PDFs. They can be viewed, measured, and used for cost estimation or simulation, butt should not be altered. Because IFC is an open standard, it is constantly evolving. 

Learn more about IFC here.


5. BCF – BIM Collaboration Format 

BCF is an open format, introduced by BuildingSMART, allowing concerns to be communicated between different BIM applications without submitting the entire model each time. The format makes it possible to keep track of issues. It also does not require the user to have licenses of all the software applications (i.e., the Designer can use the BCF that is created in a different software, simply by importing it into the BIM authoring technology).

Project members can collaborate even if they are using different BIMs because it is an open format. They can talk about concerns in a BIM by identifying locations in the models and communicating those places. The structure improves project member collaboration, lowers risks such as missing information, and speeds up the process. 

Learn more about BCF here.


6. LOD – Level of Development

The stages of development are described by the Level of Development (LOD) in BIM. It’s a set of guidelines for AEC professionals to efficiently document, communicate, and specify BIM material. LOD is a standard that outlines how a building model’s 3D geometry can be developed to various levels of refinement and is used to assess the level of service required. It indicates how much various team members can rely on information regarding a specific component.

  • LOD 100 – Conceptual / Pre-Design 
  • LOD 200 – Schematic Design
  • LOD 300 – Design Development
  • LOD 350 – Construction Documentation
  • LOD 400 – Fabrication & assembly
  • LOD 500 – Operational/As-built Models

Learn more about LOD here.


7. EIR – Employer’s Information Requirements 

EIR (Employer’s Information Requirements) is a crucial document in the BIM process, as defined by PAS1192- 2 as a “pre-tender document setting out the information to be delivered, as well as the standards and processes to be adopted by the supplier as part of the project delivery process.” As a result, it’s a good place for clients to start while working on BIM projects. The Employer’s Information Requirements document gives detailed guidelines on how to complete a construction project.

Learn more about EIR here.


8. BIM Levels

  • Level 0 – Building Information Modeling at this level simply comprises 2D CAD drawings (Computer-Aided Design). Only electronic printouts and paper are used to share files, papers, drawings, and other materials. Collaboration does not exist;
  • Level 1 – It’s not only about 2D drawings here; 3-dimensional views are also considered. Teams share information using a Common Data Environment (CDE) in level 1 BIM. As a result, they can readily collaborate on initiatives;
  • Level 2 – Everyone utilizes their own 3D CAD models, but they aren’t necessarily working on the same one. Collaboration happens between disciplines when a common file format, such as IFC (Industry Foundation Class), is used;
  • Level 3 – BIM Level 3 is a fully integrated level in which all disciplines collaborate. 

Learn more about BIM levels here.


9. BOS – Building Operating System

Also called middleware, a Building Operating System (BOS) establishes a bridge between the building equipment and external applications. The objective of BOS is to hide the building’s complexity while allowing easy access to data from the equipment. The BOS arranges and synchronizes the data from the field equipment, which is processed and translated into the correct format to fit smart building application requirements.


10. BIM Dimensions (2D, 3D, 4D, 5D, 6D, 7D) 

The Building Information Modeling dimensions are the following:

  • 2D – 2-dimension is made up of an X and Y-axis. Typically, these models are created by hand through the use of manual procedures or the use of computer-aided design (CAD) drawings;
  • 3D – 3-dimensional modeling is a computer graphics approach for creating 3D representations (x, y, and z). That includes manipulating polygons, faces, and edges to create 3D objects and surfaces;
  • 4D – 4-dimensional modeling integrates schedule data with an information model, adding the dimension of time to the project;
  • 5D – 5D BIM is about cost estimation and budget analysis. 5D BIM assists in precisely forecasting budgetary requirements and variations in material, scope, equipment, and workforce;
  • 6D – 6D BIM is related to sustainability, helping analyze a building’s energy consumption and the generation of energy estimates during the early stages of design;
  • 7D – The 7th dimension in BIM helps to manage operations and facilities. All information about the facility management process is stocked in one place (associated with the model(s)). It helps enhance the quality of service delivery throughout a project’s lifecycle.


Eva Stepak-Heritier, Marketing Director at Catenda.