Why Are Polylines Not Joining in AutoCAD?

Why Are Polylines Not Joining in AutoCAD?

If you are experiencing issues with polylines not joining in AutoCAD, you are not alone. This is a common issue faced by many users and can be quite frustrating. Fortunately, there are several reasons why this may be happening and solutions to resolve the problem.

What is a Polyline?

A polyline is a series of connected line segments or arcs that form a single object in AutoCAD. It is commonly used to represent walls, roads, and other linear features in a drawing. Polylines can be either open or closed, depending on whether the endpoints connect to form a continuous loop.

Possible Reasons for Polylines Not Joining

If your polylines are not joining as expected, there could be several factors contributing to the issue:

  • Gaps between Line Segments: One common reason for polylines not joining is the presence of small gaps between line segments. These gaps can occur due to inaccuracies during drawing or editing.
  • Different Elevation or Z-values: If the line segments have different elevation or Z-values assigned to them, they may not join properly.

    Make sure all segments have the same Z-value for them to connect.

  • Different Object Types: Polylines can only join if they are of the same object type. For example, you cannot join a polyline with a line or an arc directly.
  • Spatial Overlaps: If two polylines overlap spatially but do not share any common vertices, they will not automatically join together.

Solutions to Join Polylines

Fortunately, there are several techniques you can use to join polylines in AutoCAD:

1. Closing Gaps:

If there are small gaps between line segments, you can use the “PEDIT” command to close them. Select the polyline, enter the command, and choose the “Join” option. AutoCAD will attempt to automatically close any small gaps between segments.

2. Editing Vertices:

If the polylines overlap spatially but don’t share common vertices, you can manually edit the vertices to make them join. Use the “PEDIT” command and select the polyline.

Then choose the “Edit Vertex” option and merge adjacent vertices by selecting them and pressing “Enter. “

3. Exploding and Joining:

If the polylines are of different object types or have different Z-values, you can try exploding them into individual line segments or arcs using the “EXPLODE” command. After exploding, you can use the “PEDIT” command to join them back together as a polyline.


Polylines not joining in AutoCAD can be a frustrating issue, but with a little understanding of possible causes and some simple techniques, you can easily resolve it. Remember to check for gaps between line segments, ensure consistent Z-values, and consider object types when trying to join polylines.

By following these solutions and paying attention to detail during your drawing process, you’ll be able to create accurate and connected polylines in AutoCAD.