DWG files are a popular CAD format; from time to time you may need to input one of your existing DWG files into the Revit Architecture framework. This can be done within the software using the Link CAD button, which allows you to input a range of CAD formats, including DWG. In this video you'll learn how to use this button and how to link AutoCAD DWG files within Revit Architecture 2015.
Revit supports the import and export of many popular CAD formats. Chief among them is the DWG format used by AutoCAD. So, it's quite likely that some of your projects will have a need for at least one DWG point at some point in the project. So, in this movie, I'd like to talk about the process to link a DWG file. We can also embed the DWG, but it's much more common and usually more preferable to use the linking process. So that's what I'm going to cover here. When you link, you maintain a connection back to the original file. So if the original file has changed, you can update that link and get the latest and greatest changes directly here in Revit.
So, I'm in a file here called Link CAD. And I'm here on my Insert tab. And you can see that there are actually several different kinds of files that we can link. And in this movie, we're going to look at the Link CAD button, which gives me access to several file formats. DWG, of course, DXF, DGN, SAT files, and even SketchUp files. So since DWG is, by far the most popular, I'm going to choose that. Now I have here, a copy of the floor plan of my condominium unit drawn in AutoCAD. So, perhaps my designer worked in AutoCAD originally, and now I want to bring that AutoCAD file into Revit to begin creating the Revit project.
>> Now, if you look at the bottom of the dialog, you can see that there are several user configurable options that we have when we're linking in a CAD file. So let's talk about a few of these. The first is, if you look over here in the Preview window, you can see that the CAD file in these bright primary colors. Now that's very common in AutoCAD for people to work in those bright colors, but those colors probably wouldn't look so nice on Revit's white background. So down here, we have our color options and we can either preserve those colors, invert them but keep them in color and just kind of reverse the hues, or convert everything to black and white.
In this example, I'm going to choose the invert option, and I'll talk about why in a few moments. Now CAD files are usually organized into layers or levels. So here we can choose which of those layers or levels we want to bring in. All of them, just the visible ones, or we can even open a dialog and specify the ones we want. In this case, I'm going to leave it set to all and bring in all the layers. You can always turn off the layers you don't want later, if it turns out that there's some of them you don't want to see. Now under units, it has all the standard measuring systems that are common in architectural production.
And Revit usually does a pretty good job of auto-detecting. So that's what i'm going to leave, if for some reason it comes in at the wrong size you can always undo and then figure out what you need to suppose to choose and come choose it off of here. Occasionally you'll get an error message that displays that the lines are slightly off axis. This is just a precision calculation that Revit's doing and this check box right here corrects for that. So usually pretty good idea to leave that checked. Over here, we have an option for current view only. Keep in mind that when you're bringing in CAD data, it is not Revit data.
So revvit doesn't actually know what's in the CAD file. It's going to just treat it as just graphics. It's just going to be line work. So, with this setting, you can tell it whether or not the information should display only in the current view, or whether it should be treated more like model elements and display in all views. Now in this case I'm going to choose Current View Only. And this way if I went up to another floor plan, like second floor or third floor, I'm not going to have to worry that the floor plan for the first floor is showing through on all those levels. It also wouldn't show if I went to a 3D view or a section view or anything like that.
So, Current View Only is usually a pretty good choice for floor plans, particularly if you're planning to trace over them, which is what we're going to do in a few moments. Now over here you've got your positioning options and there's lots of choices available. Now, a pretty common thing to do is to try and match up the origins. So, I'm going to choose the Auto Origin to Origin. Now, if I move this dialog out of the way, typically the origin in a Revit project is right about here in the center of the screen. So, when we bring in this file you're going to see that it's lined up with that point right there choosing Origin, Origin.
So let me go ahead and click Open here and see what we get. Now, if I move my mouse near the file as it came in, you'll notice that it highlights with a box all the way around it. If you look at the upper right hand corner of that box, it's right about at that center point where I indicated the origin of this Revit file was. If you click to select the file, it highlights the entire file, so it's treated as one continuous piece in the Revit project. And there's this little push pin icon that appears right here that's designed to prevent you from accidentally moving this. So notice that if I tried to drag and move this file, I can't actually do that as long as it's pinned.
Now if for some reason you decided you did need to move it, you can just simply unpin it. And then you're free to move it. But I'm going to do Ctrl+Z and undo that, select it again and re-pin it. Now, in a previous movie we talked about selection toggles. And you may recall they were down at the lower right-hand corner of the screen. Or they were up here on this drop down right here. And in this case, we have both a link and a pinned element. So, if you uncheck either of these check boxes, the Select Links or the Select Pinned Elements, you will no longer be able to select this file.
Now you don't need to uncheck both of them, either one would do the trick. But as long as you uncheck one of those, not only will you be preventing people from accidentally moving the file, but they won't even be able to select it. Okay, so why did we bring in a CAD file in the first place? Well once again, maybe my designer was working in AutoCAD, but I really want to make this project in Revit. So at this point what I might do is I might take this CAD file, and I might start trying to add Revit geometry in place of the CAD geometry. Now unfortunately, there's no sort of auto-convert. You can't just push a button and convert it to Revit geometry.
But what you can do is zoom in. So I'm just going to roll my wheel here, so I can get a better look. And you can actually start to trace over this CAD file using Revit geometry. So I'm going to go to my Architecture tab, click my Wall tool. I'll change the wall type to a generic 12 inch wall. And a really nice feature about working on top of the CAD file here, is notice if you move your mouse, it kind of sees the center line between those two parallel lines in the CAD file. So, all I need to do is wait for that little dashed line to appear.
And begin clicking the points to create my wall geometry. What I'm going to do is just sort of create a little L-shape right there, and then I'll escape out. I'm still in the wall command, I only pressed Escape once. And then I'm going to come over here and choose a thinner wall, like maybe a generic five inch wall to draw some of these interior partitions. And I'll zoom in just a little bit closer, and I'm not even going to worry too much about getting these super precise. Now you can turn corners and stuff if you want, but notice that I can just sort of place some of these.
Kind of in seemingly random locations, but what we're going to do next is, we're going to use our Trim and Extend tools to clean this up. So, we've got those basic walls, and they're centered in the positions relative to the parallel lines in the CAD file. So let me Escape out of there. Now if I go to my Modify tab, I've got two tools here that I can use. The Trim and Extend Single Element or the Trim and Extend Multiple Elements. Now I'm going to choose the multiple elements in this case. This one allows me to choose a boundary edge and then extend or trim multiple elements to that boundary edge.
So for example, I could use this exterior wall over here as the boundary edge. And then notice when I hover over this wall right here, I get a little dashed line indicating that it's going to extend over, and connect itself to that wall. The boundary is still active, so if I click on a second wall, it will continue to extend over to the same location. Now at this point, I've got all the walls I wanted to extend over to that wall, and I want to choose a new boundary. So the way you do that is to just simply click an empty white space and that resets the command, but stays within it.
And then you can pick a new boundary. Now, with walls it doesn't actually matter if you click this side or this side or even the center, the entire wall will be seen as the boundary edge. Now, if you want you could click one at a time like I did a moment ago, but I'm going to do Ctrl+Z, Ctrl+Z. And it's actually a little faster to pick your boundary edge and then do a crossing window, like so, and you can select several at once. Now in this case, I only had two walls, but let me Ctrl+Z again.
Suppose I had made this selection, you can see that all three of those walls would go across. Now if I reset again, click this one, and then click here. Notice that it will actually trim it back, so this command is both a trim and an extend command. And if I drag through these two, the boundary edge was still active and those two will extend out. So you could start to see the reason now why I chose a color option to import the CAD file.
Notice that the Revit wall geometry is in black, and it is covering up the colors as I go along. So, as I am tracing, it kind of gives me an indication of where I've been and what I still need to do. Now, the other strategy you my notice is that I'd made the walls go directly over the door openings. Well, this is because I'm drawing Revit geometry now. So, unlike CAD files where you would have to trim and stop and start in between each location, here when I simply place these Revit doors in the locations where they ought to be they automatically cut the holes in the walls.
Now finally, if I go to my little default 3D View icon right here. And kind of hold my Shift key down and spin around, notice that I'm getting live Revit geometry, full-blown 3D geometry, but the CAD file does not display in this view. And once again, that's because when I imported the CAD file I chose that Current View Only option. So you can use these CAD in a variety of ways in Revit. And in this case I showed an example where we could just very quickly use it as the basis to trace over and begin creating a Revit model.
But in some cases you might have a discipline working on your team that's not working in Revit, maybe it's a lighting designer or some other kind of collaborator that is working with you. And you could simply link that CAD file in and leave it as a permanent part of the revit project. So it's a very versatile way to work that allows you to very quickly and easily marry together both Revit and CAD geometry within the same project file.
- What is BIM?
- Understanding Revit element hierarchy
- Navigating views
- Creating a new project from a template
- Adding walls, doors, and windows
- Adding plumbing fixtures and other components
- Linking AutoCAD DWG files
- Rotating and aligning Revit links
- Working with footprint and extrusion roofs
- Adding openings
- Adding railings and extensions to stairs
- Creating stacked and curtain walls
- Hiding and isolating objects
- Adding rooms
- Creating schedule views and tags
- Adding text and dimensions
- Creating new families
- Using reference planes, parameters, and constraints
- Plotting and creating a PDF
Skill Level Beginner
Q: Which versions of Revit should I use with this course?
A: This course is written for users of Revit Architecture 2015 and Revit LT 2015. Because Revit LT does not have all of the same features as Revit Architecture, some movies in this course will not be relevant for Revit LT. Additionally, there are some topics that are relevant in both versions, but the button layout or location of those tools are different. In those cases, the features and procedures for Revit Architecture are shown in the course.