and again I ask, why not the zone tool.
Yes you can draw some other object - and if youi do it would make sense that it represent someting in the model, a flllor finish for example. Its crazy to draw a polyline to measure something only to have to delete it.
A zone has the advantage of doing many things all at the same time: its a room label, a space planning or allocation object and its smart enough to distinguish between what is the perimeter of your room defined by walls and the perimeter of your room that is not defined by walls.
The Zone tool introduced room-based quantification to ArchiCAD. If its quantifying you need, why would you go looking for a workaround?
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