Develop an understanding of the process involved in integrating a roof system into a house elevation model. Gain insights into the steps of using the trim, extend, mirror, and copy commands in the architectural software to incorporate the roof system into the house model.
Key Insights
- The article provides a comprehensive walkthrough of incorporating a roof system into an elevation model of a house. This involves the usage of multiple commands such as trim, extend, mirror, and copy in the architectural software.
- The roof system was built using a truss system typically manufactured offsite and brought onto the project. The vertical stud, two horizontal top plates, and the truss were the main components used in the construction of the roof system.
- The article also explained the process of vertically centering the house within the drawing, providing a detailed account of how to use the ‘move’ command to achieve the desired placement of the house in the model.
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We have spent the past few minutes bringing our elevation model file into our A3.1 sheet file. In a couple of minutes, I’d like to go back into the elevation model itself and start putting our roof system on, but I’d like to explain the roof system to you. This is a different house.
This is a house that we've used similar to the ones we used in CAD 101 and 201, but it's conventional wood framing where we have our studs that go vertically. We have two top plates, which are two-by-fours laid flat, and then our truss system is typically manufactured offsite and brought onto the project. What you can see, though, is I have the vertical stud, the two horizontal top plates, and here I have the truss.
Where my green axis is—my Y axis—you can see that the truss is sitting right on top of the top plate. This is where the finished floor line segment we are using in our elevation is coming from. What is the red finished floor line in our building elevation file is this top of the top plate right there.
You can see that I have a two-by-four whose base is sitting right at the corner of the outside of the building and the top of the top plate. I will now go over to my elevation model file, and I will continue working on my heavy layer. I'm going to draw a line from the end here at 12 feet, 5 feet.
That line right now is representing the bottom of the truss. I'm going to offset that by three and a half inches to represent the thickness of the truss. CTRL+S to save. I'm not going to worry about putting the plywood on top of the roof.
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We know that it would be there. I'm going to let this represent the top of the roof. I can now erase this lower line and CTRL+S to save.
I’m now showing where the top of the roof is, but I need to find out how far the roof will be extending beyond the house. I'm going to go into Layers, and I’m going to go into my Plan Model XRef, and I will turn on my Roof layer. In this file, I will map it to white so the Roof layer is white, so it will show up more clearly for us.
You can see there's the roof. If I now draw a line from the end here straight down, and then extend that line, this line segment here now shows how far the truss system will extend beyond the edge of the house. I can now erase the guideline.
We're going to be using a two-by-six, so I'm just going to offset this line by five and a half inches and go down. CTRL+S to save. I now am showing the fascia component of the house. I can now draw a line from the end straight down, and I can extend it to this line, the lower segment of the roof, and then trim.
I'm going to use the Extend command just to show you. I’ll say Extend. I will select this as my bounding edge, press ENTER, and then I’ll hold down Shift and click here.
When I'm in the Extend command, if I want to trim something, I can hold down Shift to trim it away. I'm just going to show you something. Here's a line, here's a line, and here's a line.
If I were to say Trim, and if this is my cutting edge, Enter to confirm, if I hold down Shift and click here, it will extend to that entity. If I now move this line from this point to this one, and again I'm in Trim, I say this is my cutting edge, Enter to confirm, and I hold down Shift, I'm actually using the Extend command. If I go to the Extend command and use this as my cutting edge, then hold down Shift and click that, it will trim it away.
It's just a little quick shortcut—sometimes you don’t have to go back and forth between Trim and Extend. You can just use the Shift key to make it work for you. I'm now going to draw a line, because I want to work on the fascia, from here straight over, and draw a line from here straight over.
I'm not worried about the length right now, because I'm going to clean that up. I just used this line here as a guideline for knowing where the edge of my eave is going to be. I can now erase this lower line, and I'm going to begin multiple copying.
You need to pay attention to some of this, but right through here is the front bedroom that pops out. What I'm going to do is copy the angled line from the extension of the wall and the plate line over to here. Then I have my garage doors, and it's extending over to there.
I'm then going to copy this segment from end to end to end over here at the garage, and I'm going to do some mirroring. I'm going to draw a line from boundary—from here to here, which are the outside perimeters of the bedroom pop-out. I will now say Mirror.
I will select this segment and this one, press ENTER to confirm, and mirror from the midpoint of that angled line straight up. I'm now going to trim. I'll do it the conventional way—use Trim with a crossing selection to remove that.
I can also say Trim, and choose these line segments because they will be concealed behind the fascia. Then I’m going to erase this line here. CTRL+S to save. Going to do a similar thing at the garage.
I will draw a line from the plate at the top to the plate at the bottom, and I will mirror a window and this entity from the midpoint of the angled line straight up. Fillet, F then Enter for Fillet. I look at my radius—set to zero.
Pick, pick, Enter. I'm going to choose Trim, select this, and remove these entities. Once again, come into Trim, and I will select these entities right there, then erase—E space bar for Erase—and remove that geometry.
We've gotten the basics for the elevation done. I now need to continue working on the roof. You can see that I have a hip going on right through here, and the peak of the hip is right here.
So I'm going to draw a line from the peak here straight down, and I will extend. Let’s do it the new way. I'll use the Trim command, press ENTER, and then hold down Shift and click to there.
Now, this part of the roof here goes straight across, and then it rises again up here. So I'm going to draw a line from where it's rising, pull that down, and I will draw a line from here perpendicular. I will Trim.
Here's my cutting edge—get rid of that. I can now erase these two lines, and I'm going to copy the angle from there up to there, because again, if you look at the roof, you can see it’s still going up, and it’s going to rise to this point.
It will go horizontal and begin sloping down over here. So I'm going to draw a line at the top of the roof, and I will draw a line from the intersection straight over. Trim—select the cutting edges. Here's the cutting edge.
I can now erase those segments. CTRL+S to save. What I'd like to do now—you can see how the roof is at its highest point here.
It's going to slope down to here. So I'm going to draw a line from here straight down. I will mirror the angled line from the midpoint straight up.
I will extend. Let’s just play with Trim the new way. Trim here, press ENTER to confirm.
Hold down Shift, which activates Extend mode. Now, what I have going on is that my roof peaks here but actually slopes down to reach that area there, which is why we see this drop in the elevation right there. So everything looks good.
I'm going to erase this segment. CTRL+S to save. Let's zoom in and make sure our elevation looks clean.
CTRL+S to save. Now what I’m noticing is that this is the box area I have available for the roof, but the house is not really vertically centered, because when I first placed the ground line, I have to admit I chose an arbitrary distance. So what I'm going to do is draw a line from the end here to the end over here, and a line from the midpoint of the top perpendicular to, say, the ground line.
Then I'm going to move my house—press ENTER—from the midpoint of this vertical line to the midpoint of the angled line. So I've dropped the house down, and now the residence is centered vertically within the drawing. I will erase the construction lines.
CTRL+S to save. I’d like to do a little more cleanup before we wrap up this video. So here’s Trim.
Here’s the cutting edge. Press ENTER to confirm selection. Trim that away.
Trim. This is the cutting edge. Select that.
Zoom Extents. Pan. CTRL+S to save.
Let’s go back to our A301 drawing. Let’s reload the XRef. You can see the house moved down.
It is now appropriately centered in the space we’ve made available for it. So enjoy working on this, and I will see you in a few more minutes.
