Revit Content: Build or Buy?
According to Autodesk, BIM (Building Information Modeling) “is an intelligent model-based process that provides insight to help you plan, design, construct, and manage buildings and infrastructure.”
Let’s focus on the intelligent model portion of BIM, it’s really the “I” (or Information) part of BIM.
It requires content to provide an LOD 400 level model and that goes for any BIM platform, not just Autodesk® Revit® MEP.
Now let’s talk the difference between Building and Buying content.
Build Content
When I first started on my BIM path I worked for a MEP contractor that spent more than $200,000 on Fabrication CADmep, ESTmep, and CAMduct software. We had three weeks of training and were provided a database of just over 40,000 MEP items of content.
We knew the content didn’t match the manufacturers’ for our workflow, but we decided to move forward and build the content we needed regardless. We wanted to build items with more information than just the correct geometry. We wanted as much information as we could provide in the drawing including weights, cost, manufacturer, order number, and so on.
Figure 1
Figure 2
We quickly realized that building the content we required for our company was going to take months.
We had a two-man team; one team member would build the content geometry and the other member would apply the data information and then verify that the dimensions were correct per the manufacturer’s cut sheet.
After seven months of creating content and applying the data information, we could then create our database of mechanical systems. It took an additional four months of going back and forth with the team to finalize on a database and complete training.
After roughly a year we were running like a well-oiled machine.
As I look back on the undertaking I still cringe. I remember the headache I would get when someone would ask for a new piece of job-specific content.
Those who have built content understand it takes a lot of effort and time to build the content. Maintaining the content is another issue we don’t quite realize.
After I took the opportunity to move into software side of the world, the contractor I worked for didn’t maintain the content. The content we spent a year creating became corrupt and unmanageable.
This confirmed that content unmanaged can quickly turn into a poor investment.
Unmanaged content is a ticking time bomb and sooner or later it will go off. For example, the piping manufacturer Charlotte recently had a new update to its PDF cut sheets. The old cut sheet has Part No. 302 listed at having sizes 1-1/4” through 8”. The new PDF has 1-1/4” through 16”; it now has an additional four sizes available (highlighted in green). That’s the easy one to notice, but if you take a closer look at the two cut sheets, Charlotte also modified four dimensions (highlighted in yellow). The modification changed some of the fittings to be an additional 3/16” longer than before. Now this was just one of the 877 fittings on the PDF cut sheet update. Do you currently have someone checking your manufacturers’ content line by line? If that person is you and you didn’t know about the Charlotte change, you’re welcome.
Buy Content
Key factors for a successful BIM project are speed and accuracy. Content falls under both speed and accuracy.
Managed content has been made more accessible and affordable, thanks to the cloud. To have someone spend months building content just doesn’t make economic sense. Why, as BIM managers, do we rebuild Rome, when we can download Rome in a day? Change is the biggest factor of people adopting new methods of a content solution. The other is trying to prove self-worth as a BIM manager. I know the BIM managers reading this probably don’t agree, but why would I pay someone a yearly salary to build content when you can buy it at a fraction of the cost?
The main focus of a BIM project for construction is to coordinate LOD 400 content for prefabrication. It’s not to spend months building content. The focus should be on creating a clash-free model.
Equipment manufacturers have really taken on the responsibility of building Revit families (B&G, Carrier, Trane, and others). MEP manufacturers have content, but not many. Charlotte, Greenheck, and Victaulic are a few.
Now there are lots of Revit families online to download, but not all of them reach the LOD 400 level that we need for construction.
Content and connectivity is the biggest issue with Revit.
Revit Content LOD 200 versus Managed Content LOD 400
To put this bluntly, the content provided out of the Revit box for construction is what I call cartoon fittings. Basically contractors can’t use the model for construction. In Figure 3, Example A was created from Revit out-of-the-box content. Example B and example C were created with LOD 400 content. The main difference between the B and C examples is the method of the mechanical system. Example B is modeled with a grooved by press fit mechanical system, which uses Victaulic and Viega specific manufacturer content. Example C is modeled with a welded by soldered mechanical system, which uses Weldbend and Nibco specific manufacturer content. As you can see, the dimensions would be completely different between an LOD 200 model compared to an LOD 400 model. Let’s say an average Revit MEP family takes four hours to create. Example B has 11 families that would need to be built by a BIM manager. That’s 44 hours just for example B and, in turn, would be an additional 44 hours to build the content for example C. Now take 88 hours by the hourly rate of your content builder. Building content internally adds up quickly.
Figure 3
The “I” In BIM
Content today isn’t just about the geometry. As you can see in Figure 4, the first table provides little to no information about the items modeled (Red Numbers in Example A). The second table is the information provided by managed content (Green Numbers in Example B). It’s up to you to decide whether to build a cage in shark-infested waters or have a prebuilt cage waiting for you.
Figure 4
