Cleaning Up Geometry and Building Interior Walls Step-by-Step in Your Floor Plan Project

Tackle interior walls with precision—learn how to clean up stray geometry, use offsets, trims, and extends, and organize your floor plan into manageable zones for efficient drafting.

Learn about the process of constructing interior walls for a project in AutoCAD 2021. This article provides a step-by-step guide on wall construction, detailing the necessary steps including extending and trimming lines, offsetting distances, and managing wall joints.

Key Insights

  • Constructing walls in AutoCAD involves several specific steps such as extending and trimming lines, offsetting specific distances, and managing wall joints for a seamless project workflow.
  • It's important to maintain good housekeeping practices in your project, such as cleaning up wall joints as you progress and ensuring that you do not leave unfinished geometry behind. This ensures that you have a good representation of the project at all times.
  • When approaching a floor plan, it is beneficial to prioritize structurally important walls or walls that run through the entire building. Also, it's wise to utilize and extend any existing exterior wall geometry before moving on to other parts of the building.

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In this video, we are going to begin to work on the interior walls for this project. Let's get started with the elephant in the room, this extra bit of geometry that we have hanging out in space.

Now, when we're working through this project, we want to make sure that we always save our drawing at a point where we have a good representation of the project. Now, this line is clearly a working piece in our drawing. But at the moment, it could represent a roof plane, it could represent a wall, it could represent really anything.

So I want to take care of it first. Also, as a best practice, as we work through our walls, we want to clean up our wall joints as we go. Remember, who knows when you're going to stop working on a project halfway through or when the client might request a check set, you want to make sure that you have something to at all times, and that you don't accidentally leave geometry behind as you work.

So let's get started on this wall, we see that it connects up to this wall, and that it's a total length of 12 feet six, and that it's kind of hanging out by itself. We need to make sure to offset it to the left an additional six inches. Let's start with our extend.

I'll go to extend under trim. And in AutoCAD 2021, it will automatically extend without selecting cutting edges. So I'll click on the top of my line to extend it.

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Enter to say that I'm done. Now let's do our 12 feet six inch offset. I'll go O on the keyboard, O for offset and hit ENTER.

You can always use the offset button if you're more comfortable. I'll go 12 feet six inches. Enter.

And I'll zoom in and choose the bottom edge here. Offset down and click. Enter to say I'm done.

Enter to go back in. Let's offset a distance of six. Enter.

From the vertical line and to the left. We can see the dimension on our handout goes to this corner up here. So that offset needed to go to the left.

Enter to say that I'm done. Now we cannot use fillet here. I'll show why in an example.

If we use fillet, I'll click this line and this line, then the line over here gets totally erased. And that's because fillet stops at that point. So here it's better to use trim.

I'll go up and choose trim. Remember trim will automatically select my cutting edges. In this case, none of the geometry overlaps, so it's okay.

I'll click, click, click, and click. I'll zoom in and click this point here. Zoom out.

Hit ENTER to say that I'm done. Control S to save. Okay, so that was clearly the elephant in the room.

But when we're approaching a floor plan like this, what else can we do? Where do we start drawing our walls? Well, some best practice guidelines are if there's a wall that runs through the entire building or is structurally very important, and you'll know these walls when you see them, then that's a great place to start. Additionally, any walls that are already partially drawn using our exterior wall geometry, we can continue. So for instance, this garage wall actually goes all the way through to this edge if we check the handout.

Now it's broken by two doors, but that's okay. We just want to focus on the walls. We'll add the door openings later.

So let's start here with these two lines. I'll go to extend. I'll do B for boundary edges.

Enter. I'll choose this interior right there. Enter to say I'm done.

Then I'll choose this line and this line and hit ENTER to say that I'm done. Now I'm going to zoom in and trim. Trim is T, R, enter.

T, R, enter on the keyboard. Here, I'm just going to click one, two, and three. Enter to say I'm done.

Again, you can use the trim button, but we're going to use T, R, enter for trim moving forward. So that's an easy one, using the geometry of the walls that are already existing on the outside of the building. Right now, there aren't that many other exterior walls we could use, so let's focus on a very long wall.

This one right here. It runs through the entire building all the way down, and from this top corner, we can see that it's an offset in of five feet, seven and a half, and that goes to the right side of that wall. So let's go offset.

That's five feet, 7.5. Enter. That's from the exterior corner and to the right. Click.

Enter to say I'm done. I'm going to do enter to go back in, and that's because I can create the other side right away. That's a distance of six.

Enter. And that goes back to the left. Click.

Enter to say I'm done. Let's zoom in and trim this top portion out. I'll go T, R, enter.

One, two, three. Enter to say that I'm done. Okay.

And now that simply extends all the way to this bottom edge. I'll do extend, which is E, X, enter. One, two.

Enter to say I'm done. Zoom in. T, R, enter for trim.

T, R, enter. And I'll trim that piece away. Enter to say I'm done.

Zoom extends and control S to save. Now we've split the building up into three rough zones. The garage, this side here, which includes the master bath and two bedrooms and the Jack and Jill bath, and the rest of the house.

Now we can attack these zones one at a time, adding walls as needed, and it makes the project a little bit easier. In the next video, we're going to start on this part of the floor plan. See you there.

photo of David Sellers

David Sellers

David has a Bachelor of Architecture Degree from Penn State University and a MBA from Point Loma Nazarene University. He has been teaching Autodesk programs for over 10 years and enjoys working and teaching in the architectural industry. In addition to working with the Autodesk suite, he has significant experience in 3D modeling, the Adobe Creative Suite, Bluebeam Revu, and SketchUp. David enjoys spending his free time with his wife, biking, hanging out with his kids, and listening to audiobooks by the fire.

  • Licensed Architect
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  • Autodesk Certified Professional: AutoCAD, Revit, Fusion 360
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