The zone will reduce around a column but only if the walls still form a continuous boundary.
So if your column has a stronger Building Material than the wall it will cut the wall away in plan.
Or add a zone boundary line as you suggested.
But I agree the column should act as the boundary itself - seeing as it has a setting to act as a zone boundary.
There may be times when you want to model wall between the columns rather than continuous wall with the columns cutting them.
Barry.
One of the forum moderators.
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