When you open the door that connects two adjacent rooms but continue to see the wall between the two rooms, the first thing to do is update your view with the Update View button found in the Navigation tab of the Ribbon.
If that doesn’t resolve the issue, the width of the walls of the two adjacent rooms most likely has two different values. To check if this is the case, hover over the interior of the dividing wall: if the walls are highlighted in blue, they have different widths, while highlighted in red means that they have the same width.
If they have different widths, right click on the first wall and select Width to set the correct value, repeating the same action for the second wall.
For any opening (door or window) to be displayed corrected in both rooms, the width of the walls of the two adjacent rooms must be equal.
We always recommend using the Subdivide Room command to subdivide your floorplan into single rooms.
This article is valid in versions prior to 2018