I should have said that the reference lines can not touch - otherwise it automatically trims again.
You need to create the gap between the reference lines so the walls don't think they are touching.
So in this example it wont work for a short wall on the left.
You would have to move the reference line of the vertical wall to the centre away from the edges.
Then the short walls can touch either side - cut them back if they automatically trim as explained before.
Barry.
One of the forum moderators.
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