Friday, March 28, 2008

Is Revit BIM???

Whenever I say the word Revit people assume I'm talking Building Information Modeling (BIM). Most people I know think Revit is BIM. I'm sorry to tell everyone, but Revit is not BIM. Revit is one of many BIM tools. Autocad MEP is also a BIM tool as well as Archicad, Navisworks, and even Microstation.

Revit is 3d/2d Modeling program that has a powerful database at it's core. I know, "Isn't a building database essentially what information modeling is?" Don't get me wrong Revit is one of a handful of programs that is kick starting the BIM movement. Right now it is mainly used by designers & contractors, therefore it's only being used for the upfront part of the building process. But BIM is suppose to be for the life cycle of the building. BIM is not just for figuring out the initial cost of the building. It is not a tool just to figure out what the building looks like. BIM is about both of these items plus it is about information. I've said this before, but BIM is a digital representation of the physical structure as such it should have all of the data about the building stored in it's database. Revit does that right? Yes it has the capability to input all of the data that pertains to the building as long as all of those parameters are built into the model, and documented.

Let me ask you this, when you are adding your roof system to your Revit model are you filling out who the manufacture of the roof will be, are you documenting who the contractor will be, are you documenting who the consulting engineers are, are you documenting the make and model number of the paper towel dispensers. For most people I know they would answer those questions as an emphatic NO of course not, that information is in the specifications we don't need to put it in the drawings. Information is the key word there, Building Information Modeling should be a repository of all of the digital information that makes up the physical building in one place.

So lets say five years down the road the building god forbids has a water leak and some of the ceiling tiles were damaged. The owner of the building has to go to his storage room and hope he kept all of the shop drawing and warranty information that the contractor provided him, so he can contact the right people to first fix the roof and second to replace the ceiling tiles. This could take days just to find the correct information. With BIM this information is right in the database of the model. The owner open the model selects the roof, and with in it's properties it shows manufacturer of the roof, it shows the length of the warranty, and a date when the warranty is up. So BIM is much more than Revit.


David said...

Revit is a Building Information Model in the sense that it attempts to accurately model the physical a meta-data characteristics of a building. The fact that it currently does not record all information about a building doesn't mean that it is not a BIM.

The problem you have touched upon is that a single BIM cannot possibly hold all the information related to a building. Unfortunately this problem gets compounded when considered across its entire building life-cycle. This limitation stems from the fact a single software product cannot hope to cover the infinite gamut of information needs posed by the building process. To overcome this the industry needs to either:

(a) Establish some means of integrating and interoperating between different BIM systems.

(b) Establish a meta-fabric like the Web which enables BIM systems to accurately and reliably reference other information points like the ones you identify.

Option (a) is a very difficult proposition given the level of vendor competition within the AEC marketplace. Industry Foundation Classes have been around for a while to facilitate interoperability between BIM systems, but the reliability of this format is flakey at best.

Personally I think BIM is just a stepping stone towards a broader concept around information management within the digital building industry. This industry has yet to fully embrace the principles behind the Web and once (if) it does the possibility of digitally solving the problems you identify will become more of a practical reality.

Revit is one of the best implementations of BIM available today. Unfortunately this only demonstrates that the concept of complete building information management is as elusive as ever.

mamiller said...

David thank you for your input. I agree with you that Revit is one of the best implamentation of BIM today. I just get frustrated with people that use BIM and Revit interchangeably, since BIM is a concept yet to be achived and Revit is one tool out of many that support the idea of BIM.

Georgia tech has a web site devoted to BIM, they even have a list of programs that support the BIM concept.

Savoya said...

As far as I am aware, Revit is indeed the closest to BIM at this particular moment. The problem addressed here is not if this is REALLY the tool, but how people use it. Which is the main problem for me: the tool is available and it is a REAL BIM, just, user have still the same approach to it as to a standardised CAD software, and until this paradigm shift happens, you will have a real software BIM but not a really lived BIM.

Anonymous said...

Architectural Drafter using BIM in the real world here. What you mean is BIM is not Revit. I assure you Revit is a BIM software tool. When I create a set of drawings with Revit, it contains all of the BUILDING INFORMATION, thus it is a BUILDING INFORMATION MODEL.

mamiller said...

Yes Revit is a BIM authoring tool. It is one of many tools to create a Building Information Model. The point here is don't use the word Revit interchangeably with BIM. Revit is a tool to achieve BIM, but you can also draw in Reivt and have absolutely no information as well. There are some people out there that use Revit as a 3d drafting tool with out putting one bit of information about the buildings except geometric information, which makes it no better then a static physical model.