Collaboration. Although the word itself is not in words behind the acronym BIM, it is indelibly inherent in the process of producing a BIM. Think about it: how could you possibly produce a usable BIM without collaboration? At the very least, for the MEP trade, BIM means designing systems within an environment that screams for collaboration. “What do you mean the ductwork cannot fit through this area of the building?”
However, collaboration in a BIM world is far more than just designing systems that fit in a model of the building. This definition of collaboration, from Merriam-Webster, is particularly compelling to this discussion: “to work jointly with others or together especially in an intellectual endeavor.”
What are the impacts of collaboration in the process of producing a BIM using Autodesk Revit? What can we do as consultants to promote collaboration? Is the industry doomed to repeat the same mistakes as we did in the past, because we sacrifice collaboration for the sake of expediency?
Collaboration in a Revit Project
Let’s face it. A BIM project won’t be successful unless the team understands:
- How the models will be produced
- Why the models are being created
- What the consumers of the models expect
Collaboration plays a key role in all three aspects. Collaboration is essential while producing the models so that time and effort are not wasted redoing work because of unclear workflow or failure to comply with modeling best practices. If there is no clear reason why the models are being produced, then the team has not collaborated to understand how the models will work together. Also, when the design team has no idea how the models will be consumed, then collaboration has been skipped and ill-defined expectations for the model will not be met.
An important part to understanding how models will be produced is the BIM Project Execution Plan (PxP). However, I am not a fan of many of the PxPs I’ve reviewed in the last few years. Why is that? Most PxPs attempt to describe in words or tables what can only be described as complex relationships. The result is a massive document with tiny nuggets of valuable information concealed in a morass of verbiage. I’m not saying that PxPs should be discarded. They do attempt to lock in the details of how the models will be used. They usually describe why the models are being created, albeit in a boilerplate approach. Finally, some PxPs do document what the consumers of the models expect of the models. However, we are talking about collaboration in a BIM world, especially with Revit projects. The PxP will describe the LOD for the elements in the models, but what else do you need?
What information do you really need to set up or maintain your Revit models? What are the issues you run into, project after project, that you need to communicate to the rest of the project team regarding Revit models? How can you cut through the morass of documentation in a PxP to expose the critical information?
A History of the BIM Kick-Off FAQ
I developed a short document called the BIM Kick-Off Meeting FAQ in response to our project managers’ request for a document to use in early meetings to discuss issues related to BIM and Revit when they didn’t necessarily have the technical expertise with Revit itself. Another reason for producing the FAQ was that we kept seeing the same issues arise in project after project and we wanted to make sure that the consultants’ concerns were discussed before something happened to the models that resulted in expensive and needless rework.
As I saw it, the problem with the PxP is that it is rarely complete by the time the MEP team needs to start their models. In many cases, it is too late to address collaboration concerns once the MEP models are started. There is a need for a document that can be circulated to the design team before they start their models.
The FAQ served this purpose, too, because most of the questions are valuable to the entire team and not just the project managers. Another advantage to the FAQ is that it could be available to a design team that did not have a PxP for a specific project.
Ironically, in some cases, when presented with the FAQ, the client would quake at the number of questions they needed to answer. True, the answers to some of the questions might be found in the PxP, but many are not. As you can see, most of these questions are critical for getting the Revit models started on a consistent footing and with clear expectations of specific workflows due to limitations in the Revit product. Despite some amount of reticence, many clients and consultants who have seen this FAQ have embraced it and incorporated it into their own project set up process. Due to the evolution of this document in the past two years I now call it the BIM Kick-off FAQ because it is not just about the BIM Kick-off Meeting (that alone can be another article on collaboration!).
The BIM Kick-off FAQ
The following is the list of questions in the current FAQ. The FAQ has gone through several revisions with input from the Seattle CAD/BIM Managers Roundtable and other MEP consultants across the world. A copy of the actual BIM Kick-off FAQ document can be found on AUGI’s Revit forums by searching for “BIM Kick-off FAQ.”
- What is the Revit version for the start of the project?
- What is the plan for upgrading the models when new versions of Revit become available?
- Are there BIM guidelines/requirements for this project?
- What are the definitions for each Level of Development (LOD) for the project?
- What is the LOD expectation for design models?
- What is the upload schedule for the architectural models?
- What is the upload schedule for the consultant models?
- Is there a separate upload schedule for contractor coordination?
- What method/process will be used for file exchange?
- Is there a model filename guideline?
- Is there a sheet naming/sheet grouping guideline?
- Is there a workset naming guideline?
- What model (specific filename) should be used to copy Project Information into the consultants’ model?
- Considering Project Information, are all the Project Information parameters in the model correct, including Project Address and (under Energy Settings) Building Type and Location?
- From which model (specific filename) should levels be monitored?
- From which model (specific filename) should grids be monitored?
- In which model(s) (specific filenames) are the room elements to be used for coordinating the MEP spaces?
- Which linked model(s) (specific filenames) are to be set to room bounding by the consultants?
- Will all areas be defined as rooms with fully closed boundaries before MEP models are to be set up?
- Are the ceilings going to be modeled before the first consultants’ model upload is due?
- Will the architect set ceilings to be non-room bounding elements?
- What model(s) (specific filenames) are required to compose the typical background?
- If the architectural model is split between multiple models (e.g., Core & Shell and Interior or Building A and Building B) how will sheet numbering and revision numbering be handled for consultants’ single models?
- Are linked DWG files going to be used as part of the backgrounds for consultants?
If so, are they located in the same upload folder as the Revit models?
If so, have the DWG files been verified to be dimensionally correct?
- Which coordinate system is going to be used for coordination exports?
Origin to Origin
Shared Coordinates (recommended)
- What model (specific filename) should be used to acquire coordinates?
- Unless otherwise specified, will the team link Revit models using the following procedure?
Link the model documented in question 26 first, using origin-to-origin.
Acquire coordinates from the model documented in question 26.
Link all other models using origin-to-origin.
- What is the angle from Project North to True North?
- What is the direction of the Project North arrow on the sheets?
- What elements can be used to determine accurate linked model location, e.g. the intersection of Grids A/1 and Level 1?
What is the reported E/W coordinate?
What is the reported N/S coordinate?
What is the reported elevation?
- Will the team agree to perform the following before uploading models?
- Are all links in the models going to be overlay type links? (Attached links cannot be removed when the host model is linked.)
- Does the architect agree to not change the elevation of levels after models are linked? If elevations do need to change then the changes must be communicated in writing with detailed instructions.
- Does the team agree that the project base point will not be moved after the models are linked?
- What are the documented coordinates (documented outside of Revit) of the project’s base point?
Detach from Central with Audit selected
Remove unneeded linked files
Ungroup all elements (improves model performance)
- What is the project titleblock’s external family’s filename (RFA)?
- Are all models going to be central models? (This must be true in order to turn off levels/grids in linked models using worksets.)
- Does the entire team agree to put levels and grids in the Shared Levels and Grids workset?
- Does the entire team agree to put reference planes, scope boxes, and match lines in the Shared Levels and Grids workset?
- What is the scale for the majority of the plan sheets (not overall plans or enlarged plans)?
- Will the model be split across multiple sheets?
- Will project phases be required?
- Have all design options been resolved? (Revit MEP cannot create systems with elements in design options.)
- If alternates are part of the construction documents, how will the consultants be expected to produce the models of the alternates (systems cannot connect to elements in design options, see question 43.)
- RCP Coordination, which approach will the architect be using?
Consultant shall provide families for architect’s use and then the consultant shall copy/monitor the elements placed in the architect’s model (c/m elements in the models should be placed in a specific workset.)
Directly use consultant's linked model.
Architect shall copy/monitor of consultant's linked model's elements (c/m elements in the models should be placed in a specific workset.)
Place duplicated elements (place duplicated elements in a specific workset.)
- If an exact view position on sheets is required, will the architect set up scope boxes and a titleblock family with location markers before sheet setup by the consultants?
- Will the architect provide a view per level that is specifically for consultants’ backgrounds and updated throughout the life of the project?
- Will the backgrounds be complete enough (2-line walls, doors, windows, casework, fill patterns, etc.) when the view’s detail level is set to Coarse? (Coarse detail level is often used in MEP views.)
- Does the architect agree to use the Coarse Scale Fill Pattern property for displaying fire-rated walls? (All other techniques fail for linked models.)
- Contact information for each Project manager (add others as required):
- Contact information for each BIM Lead (or Manager):
As you can see from the list above there are many questions that need to be answered for any Revit project, regardless of the ultimate purpose of the BIM. When there is little collaboration early in the project there can be significant issues with the Revit models throughout the life of the project when assumptions are made. Remember the definition of the word collaboration? Use the BIM Kick-off FAQ to promote a clear understanding of your Revit projects with the other members of the design team.