Revit 2013/AutoCAD MEP 2013 IFC Improvements

This post is part of an AU class this year, MP1465, Supercharge Your AutoCAD® MEP 2013. It came up as we started working with outside vendors that are solid AutoCAD MEP users, but not Revit users - and that's what we're using.

First up, know the rules:
- Architecture and Structure items convert pretty nicely, with ACAD Arch walls converting to Revit walls. You may need to swap some styles, check justifications, etc. but getting the overall model works pretty well.
- MEP objects come into Revit from ACAD MEP as in-place families, but if you setup your import options, and have your classification definitions assigned to MEP objects in ACAD MEP, then they come in as "pipes, pipe fittings, duct, etc.". Be aware - they don't have the same behavior as a duct, pipe, etc. that was created with native Revit tools. But you can add connectors as needed to make these types of connections.

Here's the excerpt from the class (or as I like to call it, the "tease")...

IFC stands for Industry Foundation Class, and it’s a file format that is universally shared between CAD platforms. The intent is that an object in a program like AutoCAD MEP can be converted into the same type of object in Revit, or other BIM applications.

In order for an object to be exported to IFC, it has to have an object classification assigned. To look at the default styles go to ProgramData\Autodesk\MEP 2013\enu\Styles directory and open the IfcShareBldgElements (MEP).dwg file.

 

In the style manager, look at the classification definitions under Multi-purpose objects. IFC properties can be assigned to these objects:

 



Once the items are selected, the classifications tab lists the information associated with an MEP object that will be exported:

 

To use these in a file, and assign them to MEP objects, you have to copy them into your current drawing. Use copy and paste in the style manager to add both classification definitions to the current drawing.

Select OK to exit the style manager. Now that they’re in the drawing, you can edit the properties of objects to assign the classification. I’ll grab the ductwork, and then go to the properties palette:

For most other parts, IFC Type Classifications are mapped to MvPart Objects (such as equipment, panels, and devices) automatically. This classification is added in the Autodesk Catalog Editor by default. You can modify this classification or add more classifications to the content library in the Autodesk Catalog Editor.

Once you’ve added the correct classifications to MEP objects, review the IFC export settings. From the application menu, select the Export tool, and then select IFC. The options are located on the export dialog, and the object tab lists all objects that loaded into a drawing – you can choose to add or remove objects as needed.

After you review the options, you can run the export. The IFC file is created in the project folder. To test this, I’m going to open the file in Revit. Before doing this, open the IFC Import options on the Application menu, under Open:

Before importing an IFC file, you need to go through and map IFC class names to Categories and sub-categories. This tells the MEP object what is used to control its display in Revit.

Once the IFC file is imported, it will appear something like this:

The imported objects take on most of the characteristics of the equivalent objects in Revit. You may need to check IFC mappings in both the AutoCAD MEP file and the Revit file during this process, but this represents a major leap in compatibility between the applications.

Be aware that imported objects may not completely take on the behavior of a normal duct. For example, the duct is treat like a duct with properties assigned, but it does not include the connection, system or sizing behavior. You have to add a connector to attach duct to it.

I don’t care what anybody says…this is really cool…

Happy BIM'ing - see you in Vegas!

zzzz....uh...huh? AU is in a week? Geez, I overslept..

Wow, where does the time go? Autodesk University (#au2012) starts classes one week from today...and the last couple of months have been crazy, getting all of the handouts, datasets, powerpoints, props, home movies, etc. finished. But I'm about there...

And when you finally get a moment to reflect, you hope you've put something together that really hits home with users. This year's approach was a little different - I wanted to find what the really obscure little things were that come up as support issues, and get them addressed. But I also needed to hit on the bigger picture, and make sure that the day to day items - using systems, making families quickly from scratch, or from manufacturer's content, etc.

And then I an email from an engineer I know, saying that he doesn't think MEP BIM is ready for primetime yet. And I couldn't disagree more, but if you don't train your staff for a few years, then, yeah - you're likely to have the same attitude. So here's what I think - Revit MEP 2013 and AutoCAD MEP 2013 represent the best two MEP design applications on the market, hands down. Both have their strengths, but both require you to make some changes to your design process.

Here's an example. In one of my classes, we talk about adding an instrument connection to a duct or pipe. The instinct says, add a tap. Instead, if we're making this connection at a fitting, such as a duct tee or flowmeter, why not add the physical connection to that component? It will stay connected to the part, if the part moves or changes size, the connection is still there. It can be fabricated into the part prior to being added in the field, so that may save a little "field fit and finish" time.

That's one of the challenges that comes with BIM. If you're still in the drafting mentality, then all you're thinking about is a line or circle - but in BIM, you HAVE to think more from a DESIGN standpoint. It's all about making a more easily constructable building, that's more sustainable while allowing for creativity in the design.

The beauty of AU is that it's a gathering of like minds, that are looking for that tip, or method, that helps you stay current with technology, or gain that competitive advantage. We're driven to find better ways to leverage our tools, and make life easier for ourselves (as though it isn't already). And we really want to find ways to interconnect all of this information, and come up with the big picture, that satisfies the client's and end users needs (think airport electrical outlets).

So take a little time this week - network with your peers, get to know some of the industry leaders, and take advantage of some of the best and most passionate instructors in the world. We'll all be hanging out in the same place - so come by, say hello, and let's talk about the future. And if you can't make it, check our AU Virtual - last year, tens of thousands did - so the learning doesn't stop on November 30th. I'm ready - are you?

See you in Vegas!