The OFFSET command creates parallel copies of an object away from the original object.

Here’s the scenario – You have an electrical drawing with limited space. You also have an oddly shaped electrical box that requires a 4 foot space between it and anything else around it.

Since the drawing is tight on room, you want to make sure that you adhere to the recommended space requirements but you also need to maximize efficiency.

Below is the oddly shaped electrical box. It is represented by a polyline

When you offset the polyline by 4 feet, it creates a parallel copy around the polyline (shown below)

But after further inspection, you notice that not all of the outer polyline is really 4 feet away from the electrical box.

(Below) The sections of the outer polyline that touch the green areas are 4 feet away, but the sections of the outer poyline that touch the red areas are greater than 4 feet.

This will result in wasted space.

How do you fix this?
Change the system variable OFFSETGAPTYPE to <1>

This will create rounded edges at the corners of the polyline, thus maintaining a true offset distance of 4 feet all the way around the electrical box.

Shown below is the result of the OFFSET using OFFSETGAPTYPE set to <1>

Please note – to only use this when needed! It is not recommended to keep this setting as a permanent setting. However, it is good to know about.