And a third that uses a solid element subtract:
Create a profiled wall similar to Laszlo's first example - but just with the outside sheathing extending upwards. Place your slab on top of the core of the wall - only up to the sheathing as in real life - with the core and inside sheathing of the wall penetrating the bottom sheathing of the slab. Subtract the wall from the slab.
Karl
One of the forum moderators
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