Explore the process of constructing roof plan geometry with the help of a step-by-step tutorial. Learn how to offset and explode rectangles, draw connecting lines, fill gaps and add ridge lines as well as dimensions.
Key Insights
- The construction of roof plan geometry begins with switching to the 'A roof' layer and offsetting the rectangle where necessary. The offsetting distance is generally one foot away from the rectangle.
- Once the main structure of the roof is established, additional elements such as ridge lines and bump-outs can be added for complexity. This involves techniques like exploding rectangles, offsetting lines, and connecting midpoints.
- After the roof geometry is complete, dimensions are added to provide necessary details. The 'A roof dims' layer is used to annotate and add linear measurements, ensuring accurate representation of the roof plan.
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In this video, we will continue with our Roof Plan geometry. If we check the handout, we can see that the rest of the roof is drawn on the A-ROOF layer because it is represented with a solid line.
I'll switch my layer to A-ROOF, and now we can begin working on the rest of the geometry. If I were to offset this rectangle, it would offset by default to the A-ROOF-OUTLINE layer, but we know we can migrate that geometry like we've done with the counter in the past. So let's do that.
By checking the handout, I can see the majority of my roof distance is one foot away from this rectangle. So I can go Offset, a distance of one foot, Enter. I'll choose this geometry, make sure I click outside, and we can see two rectangles now.
I'll hit ENTER to say that I'm done. Picking the outer rectangle, I will go to my layer dropdown and choose A-ROOF. Escape, Escape, Escape, Control + S to save.
This is the majority of our roof geometry, but we can see on the bottom right that the roof bumps out an additional two feet because it is three feet from this corner. Before we can offset this line by itself, we first need to Explode this rectangle. I'll pick the rectangle and I'll choose Explode.
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Now we can Offset this line out two feet. Offset, 24 or two feet, Enter. I'll pick this line, go to the right, and click. Enter to say that I'm done.
The final bit of geometry we need to draw is the line connecting the midpoint here to the midpoint here. I'll go Line. With my running Object Snaps on, I can see the midpoint triangle—click—and the midpoint triangle—click.
Enter to say that I'm done. To make it a little easier to see in the video, I'll turn off my A-NOPLOT layer, but you can leave yours on if you'd like. Finally, we need to connect these edges.
Now we can do this with Trim and Extend, or we can do it with Fillet. In this case, Fillet is a little easier. Just remember: you are clicking on what you want to keep when you Fillet.
I'll go Fillet. I'll check my radius, make sure it says zero. Just in case, I can go R, Enter, Zero, Enter. And in this case, we have multiple.
So I'll go M, Enter. I click on what I want to keep. We can see this corner is connected, but this corner needs some work.
So I'll start here—clicking to keep and clicking to keep. Now, when I go to this corner, I see I turn right. So I click here, turn to the right, and keep this.
Then here we have a gap. So this is fairly simple. Click here and click here. Enter to say that I'm done.
One final bit of geometry is the ridge. This roof has a ridgeline running down the middle, and the slope goes down to the left and down to the right. We can see at the top of our geometry that the ridgeline is in the middle of this edge and it goes down perpendicular to the base.
If I went midpoint to midpoint—midpoint to midpoint—we can now see that that line is angled, and that's because we extended the length of this line when we used Fillet. Now let's go Line, midpoint—which is a running Object Snap—to the Shift + Right-Click Perpendicular at the bottom edge here. Enter to say that I'm done. I can Zoom Extents, Control + S to save.
And if you didn’t turn your No Plot on, just hang out, but I’ll turn my No Plot back on because the next thing we are going to do is quickly add our dimensions. I’ll go to my A-ROOF-DIMS layer. Don’t go to A-DIMS—go to A-ROOF-DIMS—and we can start adding our dimensions.
I’ll go to Annotate. I can see VDCI-Tick-48 is the style, and so I can simply begin adding my dimensions—Linear.
I’ll start here to here. I’ll pick on this geometry. I’ll go Continue to the end and click. Enter to say that I’m done.
I’ll go back to Linear and I’ll do these small one-foot markings from this point to this point there. Again, from here to here. And this time I’m going to the left. There’s one more over here on our handout.
I’ll go Linear—here and here—and up to that same line on the right side of the drawing. We can see that there are two dimensions for the height. So: Linear from this endpoint at the top to this endpoint here.
And those go to that line and snap. I can use Continue, bring it to the end here. Enter to say that I’m done. Finally, there are two one-foot dimensions here—Linear here to here and down to the line.
And again, Linear—here to here and to the side. And this dimension is probably the most important because it helped us understand that there was a one-foot space and then a two-foot space. Linear from this line to this line and down, and snap right there. Zoom Extents, Control + S to save.
Those are all the dimensions we need for this drawing. And in the next video, we are going to add our text, symbols, and our hatch pattern. I’ll see you there.
