The BIM Information Exchange refers to the information stream that is exchanged for each BIM Use identified in the BIM Process Map. Find out how to define it in this interesting insight.
BIM Process Maps are useful to identify information exchanges and the processes that need to be carried out for the different BIM Uses.
Today, we will see which method turns out to be necessary for defining the – Information Exchange – previously identified in the BIM Process Map.
What does BIM Information Exchange mean?
BIM Information Exchange means the exchange of the information content relating to each BIM Use identified in the previous design phase of the BIM Process Map.
In order to define the information exchanges, the work team accurately identifies which information needs to be implemented and to whom to transmit it for each BIM Use, and does so by analysing the project in detail. It is not said that any information of the model is indispensable for all BIM Use, the team therefore after having carefully studied the project and identified the various BIM Use, analyzes and filters the information that will be necessary for each use of the BIM.
The following image shows precisely the process that the information undergoes in the design implementation of the BIM.
From the figure above, we can see that the downstream BIM Uses are directly influenced by what is produced at an upper level.
Looking at this example: if the information model, needed to implement a particular BIM Use, is not entered by a team member upstream of the process (output), the person responsible for defining that BIM Use must therefore implement the information connected to it (input). It is therefore up to the project team to decide who will be the author of this information and at what stage of the process this information will have to be provided.
In order to simplify the process, the team identifies only one information exchange requirement for each BIM use. Despite this, there may be a need for more than one information exchange.
These additional information exchanges are identified in those maps that, in the design of the BIM process map, we will have defined detailed maps.
What is the BIM information exchange worksheet?
The BIM information exchange worksheet is a worksheet that is compiled in the early stages of the design, immediately after having created the BIM Process Map, which helps the work team in the valuable phase of selecting the information to be entered and transmitted for each BIM use.
It is very important for team members, in particular for the author and recipient of each information exchange, to clearly understand the information content to be transmitted, precisely for this purpose the BIM Information Exchange Worksheet is used.
The procedure for compiling the Information Exchange Worksheet is divided into five phases, let’s see them together in detail:
- Identification of each potential BIM Information Exchange from the BIM Process overview map: in the article on the BIM Process Map we have seen how the process involves the development of two maps with different levels of detail: the first more overview, the second instead of detail about each BIM Use. It is precisely from the more general map that the Information Exchanges that must be exchanged between the parties are identified and defined. This same overview map also determines the timing of information exchanges. In this way, the parts of the team involved are fully aware of the progress of the project and the times of reaching the BIM deliverables. In addition, when possible, the various BIM information exchanges are listed in chronological order so as to have an immediate visual representation of the progress of the BIM model requirement.
- Choice of a Model Element Breakdown Structure for the project: once the work team has selected the Information Exchange (IE), the team itself elaborates an element breakdown structure for the project, that is, an organizational structure in which it divides the model into various elements of competence generally of different professionals.
- Identification of the information requirements for each Information Exchange (IE) – output and input: for the definition of each IE BIM it is necessary to identify the following information:
- Model Receiver: team member/members that will be the recipients of the specific IE and that they will use to apply the BIM use for which they are responsible. These team members will be responsible for completing the Input Exchanges.
- Model File Type: This information requirement applies to the software and versions of such software that will be used to manage the model in relation to the various BIM uses. This step is fundamental in view of the BIM interoperability between the various IEs. For example, you will specify whether you will use an IFC 2×3 or the Edificius’ proprietary file format (.EDF).
- Setting the level of detail of the information (Information): in this step the information necessary for the implementation of the individual BIM Use is identified. Not all BIM uses require all the information which is available, so in this phase, the information is filtered in relation to the specific use of the BIM. The Information Exchange Worksheet, proposed by the BIM Project Execution Planning Guide of Penn State University, uses a structure that articulates the information content according to three different levels of detail.
- Notes: not always all the information requirements necessary for the information content of the BIM model can be met by the information and element breakdown structure, when this happens it is possible to add further descriptions in the section dedicated to the notes.
- Assignment of the parts of competence to the author responsible for the information requirement: for each entry within the Information Exchange, a member is identified who is responsible for processing the relevant information. The advice is to use abbreviations of the corresponding disciplines to make the worksheet more readable and easier to use. The following image shows a list of potential responsible members with their abbreviations:
As for the information input phase, this is identified on the basis of the needs of the model receiver and is deduced directly from the general BIM process map.
- Comparison between the information content of Input and Output: once the information requirements have been defined, the project team must compare the information content of the model created with the requirements indicated by the recipient. When you find items for which the output information (Authored) does not match the Input information (Requested), that is, when there is an inconsistency between what is requested and what is produced, you can act in two ways:
- Output Information Exchange Requirement: the author can review the information by implementing it and reaching the level of accuracy required by the recipient;
- Input Information Exchange Requirement: the recipient of the model assumes the responsibility of adding the information they deem missing and necessary for the implementation of the BIM Use.
Below is a sample excerpt from the BIM Information Exchange Worksheet, in which structural, architectural and HVAC models were created during the Design Authoring phase.
Subsequently, the content of this phase is delivered to the next step of 3D Coordination and then to that of 4D Simulation. The boxes marked in red are those that indicate a lack of correspondence between what was created by the authors of the models (Architects, Structural Engineers, HVAC Engineers) and what instead had been requested by the recipients (BIM Coordinator, General Contractor).
Which party is responsible for the Input Information Exchange?
The team member responsible for the Input Information Exchange is the one who receives (Information Receiver) the model directly from the author. The latter in turn is responsible not only for the geometric modeling, but also for the information content associated with it.
For example, the architect responsible for the architectural model implements the information content in his digital model, developing everything according to the level of detail required. Once the Design Authoring phase is completed, the information model created by the ARCH is transmitted to the next phase of 3D Coordination (as in the previous image), in which the Responsible Party (Information Receiver) is the BIM Coordinator.
If the information transmitted by the ARCH after the first phase of Design Authoring is not sufficient with respect to the information requirements required by the Model Receiver, he/she may decide to enrich the information content with the missing information or may request that it be done by the author of the model.
As you can see, in the BIM you have already planned everything from the beginning of the design process, nothing is left out and even the informative content is perfectly organized, developed and implemented carefully by the various professionals according to the competence of each of them. The result is a useful information model for the entire life cycle of the asset.
My advice is to test run the BIM software that suits your specific discipline and experience the advantages of having all relevant information linked to the various elements available and enclosed in a single digital model.