This has cropped up a few times in the past.
Here are a couple of old posts about it...
https://archicad-talk.graphisoft.com/viewtopic.php?f=11&t=61205&p=282391&hilit=ZONE+SIZE#p282391
https://archicad-talk.graphisoft.com/viewtopic.php?f=6&t=55827&p=265807&hilit=zone+dimension#p265777
The problem is zones are not always rectangular - can be any shape and any rotation.
Take for example the other bedroom in your image.
Does the zone include the robe as well, or just the recess to the main door so it is no longer rectangular?
Does the length of the room include the robe or not?
Personally I have a room dimension object that I can stretch to suit the size of the room that i want to measure.
It is not automatic (in that you have to stretch it yourself) but it then shows the exact dimensions I want.
Barry.
One of the forum moderators.
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