Creating Accurate Window Openings with Trim and Offset Tools in Your Architectural Drawings

Master precise window placement using offset and trim commands, learn to manage complex layouts, and prepare your drawings for accurate geometry insertion.

This article provides a step-by-step guide for creating window openings in an architectural design, explaining how to define the size and location of each window in accordance with the overall building layout. The guide covers how to adjust for interior wall edges, extend lines as part of the trim workflow, activate extend by using the Shift modifier key, and create extra geometry for doors.

Key Insights

  • The article demonstrates how to offset windows from the interior edge of a wall, rather than the exterior corner of a building. This can be done by extending lines as part of the trimming process.
  • When drawing window openings, the Shift modifier key can be used to activate the 'extend' command. This allows lines to be extended so that window openings can be accurately trimmed out.
  • The guide also explains how to create extra geometry for doors in the workflow. This includes offsetting to the middle of the window, then the middle of the door, before offsetting half the distance both ways for each of the windows, allowing for precise trimming of the design.

This lesson is a preview from our AutoCAD Construction Documents I Course Online (includes software) and AutoCAD Certification Online (includes software & exam). Enroll in a course for detailed lessons, live instructor support, and project-based training.

Let's continue working on our window openings. I'll zoom in up here, and we can see that this window is actually being offset from the interior edge of this wall, not the exterior corner of the building.

That's okay, we can easily extend this line as part of our trim workflow. This offset is 2' 7", so I'll go O, Enter, 2' 7", Enter. I'll click this line and come to the right, click, Enter to say I'm done, Enter to go back in.

This window is 6' Enter. I'll click the line and go to the right, click, hit ENTER to say I'm done. Now as a part of this trim command, we want to use the Shift modifier key to activate extend.

Let's see what I mean. I'll go T, R, Enter, and I want to choose Cutting Edges, T, Enter. I'll select these four lines as my cutting edges, Enter to lock it in.

Now we need these two lines to be extended so that the window opening can be trimmed out. So I'll hold Shift, we can see Shift-Select to extend, I'll hold Shift and click here and here, and then I'll release Shift and I can click to trim out here, here, and the two lines of my wall. I'll hit ENTER to say that I'm done.

Learn AutoCAD

  • Nationally accredited
  • Create your own portfolio
  • Free student software
  • Learn at your convenience
  • Authorized Autodesk training center

Learn More

I'll do that one more time, T, R, Enter for trim, T, Enter for my cutting edges, I'll select these four as my cutting edges, Enter to lock it in, then I'll hold Shift to extend this line, and I'll keep holding Shift to extend this line. When I release Shift, I am back in the trim command and I can trim out these lines and the lines on my wall. I'll hit ENTER to say that I'm done.

Let's pan down over into this section, and here we see an interesting organization. It goes window, door, window, door. And we're only going to want to make our windows right now, but in this workflow we need to create some extra geometry for the door.

We can also see that we have an interesting way to represent the offsets for these windows and the door. The dimensions are going to the middle of the window and then above we're given the total width of the window and the door. Now this might be represented in some projects as a door and window symbol, and we would need to check a reference table, which is the door schedule and the window schedule, to learn what the total width of these doors and windows are.

We don't have a door or window schedule in this course, so instead we're showing the center point of the door and window, and then we're showing what distance or what width the openings represent. So down here we're going to start by offsetting to the middle of the window, then the middle of the door, then the middle of the window. And then we'll offset half the distance both ways for each of the windows, and then we can trim out.

To start, we need to find the middle of the window relative to this wall, and we can see that's 2 feet 7 and a half inches. So I'll go O, enter for offset, 2 feet 7.5, enter. I'll choose this line and go to the left, click, enter to say I'm done, enter to go back in.

Now the next two offsets are the same, 4 feet 2 inches. 4 feet 2, enter. I'll pick this line and go to the left once, and then I'll choose my new line and go to the left again.

Enter to say I'm done. Now I'll grab all three of these lines, I'll use my move tool, and I'll click anywhere in space, drag them up with ortho on, that's F8, and I'll click to place them here. This will allow me to only trim, and I don't have to use that extend option we used in the previous workflow.

Now we're going to leave the door alone for now, and we're going to focus on the two window openings. Both of these windows are 4 feet total, so each offset here is going to be 2 feet to the left and to the right. O, enter for offset, 2 feet, enter, here to the left and here to the right, here to the left and here to the right.

Enter to say I'm done. Now I'll choose this line and this line, and delete them out. That leaves us with two window openings here and here, and this one is representing the center line of the door.

Now I'll go tr enter for trim, I'll pick these lines here and these lines here, and then through with a fence for both of those windows. Now we still have the line that we can use to create the door opening when we come back around and create the doors. The reason why I'm not going to create that door opening now is I want to see just where my windows are when I put my window geometry in.

Then I'll come around and make the door openings. Sometimes it can be difficult to remember what's a door and what's a window when there are a lot of openings on the drawing. In this workflow I'm going to do window openings, then window geometry, then door openings and door geometry.

Okay, the next two windows are over here on the corner. We can see that there is a 3-inch jam typical. Again, that represents the two 2x6s in this project, side by side, that are required when a wall meets another wall.

Now it wouldn't be required in both of these locations as there would be wood studs running up like this, but we would still need them in one of the sides and to make this corner symmetrical, we'll put a 3-inch jam typical distance on both sides of the wall. So the offset's going to be from the inside, out 3 inches, then the width of our window, which is a 2-feet wide window. I'll go O, Enter, 3, Enter, and I'm going to start by creating the window on the side here, so I'll go down from the interior here, Enter to say I'm done, Enter to go back in, 2 feet, Enter.

I'll choose this line and come down and click, Enter to say I'm done. Let's go TR, Enter to activate trim, T, Enter to select cutting edges. I'll pick all four of these lines, Enter to lock it in.

I'm going to hold Shift to activate extend here and here. I'll release Shift and I'll click, click, click, click. There we go.

Our window opening has been created here. Now we can do the same thing using this small little line and we'll create the window opening here. O, Enter for offset, 3, Enter.

I'll choose this short line here to the left and click, Enter to say I'm done, Enter to go back in, 2 feet, Enter, to the left, Enter. Now I'll go TR, Enter, T, Enter for cutting edges, picking all four of these, Enter, hold Shift to activate the extend, click, click, and then I'll trim these out. You might have to zoom in really close because those were short lines and make sure you pick the top half of the line.

Alright, there we go, CTRL S to save. We only have two more windows. They're both down here in the kitchen dining room area.

Now the cool part about these window openings is that they're going to be offset from this window edge right here. Because we've already trimmed this line down, we don't need to trim it any further. We just need to trim the openings for the windows themselves.

As we look at the handout, we can see the offset is going to be 8 feet 5, then the window is 5 feet wide, then 3 feet 10, and our final window is 3 feet 6. Let's do those offsets. O, Enter, 8 feet 5, Enter. I'll zoom way in and pick this short line.

I'll go down and click, Enter to say I'm done, Enter to go back in, 5 feet, Enter. From my new line, I'll go down and click, Enter to say I'm done, Enter to go back in, 3 feet 10, Enter. This line down, that's the top line of my new window, Enter to say I'm done, Enter to go back in, 3 feet 6, Enter.

And that is the opening of the window itself. Let's go T, R, Enter for trim, and I'll trim out between those two, and I'll trim out between those two. Enter to say I'm done.

Let's do a zoom extents, and Control-S to save. And now we are ready to add in our window geometry. We'll add our window geometry in the next video, and then we'll continue with our door openings.

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
  • Autodesk Certified Instructor (ACI SILVER– Certified > 5 Years)
  • Autodesk Certified Professional: AutoCAD, Revit, Fusion 360
  • Adobe Visual Design Specialist
  • SketchUp Certified 3D Warehouse Content Developer
More articles by David Sellers

How to Learn AutoCAD

Develop advanced skills in AutoCAD for drafting, design, and 3D modeling.

Yelp Facebook LinkedIn YouTube Twitter Instagram