- [Instructor] In this video, I want to talk about the Attach Walls feature. So with Attach Walls, you can actually take the tops or bottoms of your wall elements and attach them to other geometry. So when we look at our roof design, we can see we've got these big old gaps here up near the tops of the walls at the undersides of the roof, so I want to correct that. It turns out it's really easy to do with the Attach Walls feature. All you need to do is select one or more walls. On the ribbon, you're looking for the Attach Top and Base command. When you select it, on the Options bar, there'll be two options, Top or Base.
Well, since we want to go up to the roof, we're going to stick with top, which is the default, and then you just click anywhere on the roof. And that will attach that wall to the underside of the room. Now I'm going to do CTRL+Z and undo that because a more efficient way to do that would be to actually make a selection of several walls first. The fastest way to do that is to use chain select. So I'm going to highlight one of the exterior walls, press the TAB key, and that will do a chain all the way around the perimeter of the building.
Now, a common mistake that folks will make here is they say, yep, that's the selection they want, and then they move their mouse away to go look for the button and nothing is selected. So remember, it's highlight, TAB, click. So I'm going to highlight it again, press TAB, but before I click, I want to just show you one other thing. If you look carefully at what's highlighted, that's the perimeter of walls that I'm looking for, but notice that there's actually another possibility because there's some exterior walls on the low portion of the building as well. If I move my mouse slightly while that chain is highlighted, notice that it switches.
So instead of selecting the wall in between the two roofs, it actually changes to the three walls down around the low portion. And if I move it slightly back again, it goes back to the wall between the two roofs and de-selects the other three. So it's really important that you pay attention to which chain you're getting before you click. Once you click, then you've made the selection. So now I've got those selected, and another thing that I always like to do is look at my Properties palette right here. So it says Walls (7). Now, I could count them deliberately and make sure that's exactly the right quantity, but seven feels about right.
I've got four side of the building, plus the little L there, so seven seems okay to me. So you just want to verify that that quantity seems reasonable. If it doesn't, then you might want to stop and investigate why that is before you continue. So I've got those seven walls. Now I'll click Attach Top and Base. Again, it's going to default to top, so that's fine, and I'll click anywhere on the roof to make the attachment. Now, if I try to repeat that over here, press TAB, once again, I'm going to have two different chains to choose from.
There's one chain, but if I move slightly, it's going to do the entire building. Now again, you want to be careful here, because if I select the entire building here and go ahead and choose Attach and pick this roof, I'm going to get a bunch of errors. You see here? It says 1 of 6. What the error tells me is that the highlighted walls are attached, but they missed their target. Now, it turns out that this warning can actually be ignored, so you could click OK here and just continue, but you really don't want to have a bunch of walls attached to something that they don't touch because it's just wasting processing power in your file and, over time, that can affect the performance.
So what I'm going to do is click Cancel here and just be a little more careful about my chain selection. So instead of that chain, I'm going to move slightly and get that chain. Now, if I click, it selects the three walls around the perimeter, which is good, but notice it also selected that one in the middle there. So I'm going to hold the SHIFT key down and de-select that one wall there. And then over here, my quantity says three. So that's exactly what I want. I want the two that I can see and the one behind in this view.
I'll click Attach Top and Base and I'll click on this roof to attach those and notice there are no errors this time because everything attaches correctly to its targets. Now let's take a look at how this attachment looks in a section view. So it looks really good here in 3-D, but it's not a bad idea to check it in other views as well. So if I scroll down on the browser, I've got this Section at Lobby view. I'm going to open that up. And then I'll just zoom in in this location right here. Notice that the top edge of the wall not only attaches to the roof, but it actually cuts at the angle of the roof slope.
Now, if we select the roof and we come over here to the Properties palette, scroll down and change the slope, let's do maybe 24 degrees, notice that, as the slope increases, it changes the angle at the top of that wall as well. So that's pretty powerful. Now, in addition to that, if we come back up here to the top of the Properties, there's this Base Offset from Level feature here. It's currently at zero. So you can see that the roof hinge point is right there at zero relative to its level.
I could change this though to anything I want. So let's put in 1,000 millimeters there and watch what happens. The roof now projects up 1,000 millimeters from its level, and notice that the wall continues to stay attached. Now, here's the thing about that. If I select this wall and investigate its properties now, it's a little bit odd because the top constraint is still listed as High Roof, which is right here. And the overall height of the wall is still measuring to where the High Roof would be, or 6,000 millimeters.
It does not include that extra 1,000 millimeters at the top of the wall. So that's a little bit misleading. The only clue that you have that this wall is actually attached to anything is right here, where it says Top is Attached. Now, unfortunately, you can't uncheck that. It's a read-only property. So if you wanted to remove the attachment, what you do is actually click the Detach Top and Base button here on the ribbon, and then you just select the item you want to detach from, and the wall will drop back down to its original location.
Now what I'm going to do is CTRL+Z and CTRL+Z again to undo those last two changes. And then let me zoom out and pan over here because what I want to talk about now is the attachment feature is not limited to just roofs. You may recall that in the video where we talked about creating floor slabs, there were some questions that were asked when we were finishing the sketch. And one of those questions actually asked if we wanted to attach the walls' geometry to the undersides of the floors.
And here's an example of that right here. So even though this wall says that it goes up to this location here at Level 2, you can see it right there, it says here, just like the outside wall, that its top is attached. But in this case, it's attached to this floor element instead. So you can actually attach walls to floors, to ceilings, to roofs, and to even other walls. So the attachment feature can be very versatile and it can be very powerful. But again, just keep in mind that sometimes, the unconnected height value is a little skewed because it doesn't reflect the actual change from the attachment itself.
Paul also shows advanced techniques for modeling stairs and complex walls, adding rooms, and creating schedules. Finally, discover how to annotate your drawing so all the components are perfectly understood, and learn how to output sheets to PDF and AutoCAD.
- Understanding BIM and the 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
- Adding text and dimensions
- Creating new families
- Using reference planes, parameters, and constraints
- Plotting and creating a PDF