Here is a little tip shared by one of our AutoCAD experts, Matt, at Robert Stephen Consulting, LLC.  Enjoy!


The BPOLY command is useful to create a polyline that bounds existing geometry. It is much like the HATCH command or a paintbucket/flood-fill in a paint program.

General Usage

Often lines around a room are determined as LINEs or XLINEs. BPOLY is then used to create the polyline that fills the Remaining Area without any gaps.

After all the rooms have been PLINE’d, BPOLY is used to create circulation and other remaining spaces.


We’ve found a little problem with the BPOLY command.  The BPOLY command may skip vertexes when you use it on

  • A fairly large area
  • Containing small vertex offsets

There are two solutions:

  1. Split large areas into smaller ones (particularly large circulation spaces).
  2. Use special care to be certain that vertices align.

How big is this problem?  This appears to happen with distances on the order of 1/100,000.  It could cause your total area to be off by fractions of a percent overall.

The real problem arises when we have to track down a remaining area in a drawing and run across these little glitches.  It is becomes difficult to tell where the actual problem lies.

  • Polylines should be Concave whenever possible
  • BPOLY is view dependent, the entire area to be filled needs to be viewable on the screen before running the command.

A complicated area, like this:

Should be simplified to something like this:

As always, we hope you enjoyed our post.  Please comment below with any thoughts, feedback, or questions.  We love hearing from you!

Like what you read? Subscribe to the blog and follow us on Twitter, Facebook, and Linkedin to keep up to date with the latest news from RSC, LLC.
Thoughts? Questions? Comment below and let us know what you think! We’d love to hear your insights.

One Reply to “AutoCAD Advantages: BPOLY Command”

Leave a Reply

Your email address will not be published. Required fields are marked *