Make sure your curved roof (complex profile wall) passes over the top of your vertical wall (i.e. they must clash).
The complex profile wall needs to have a stronger priority strength (or Building Material - you don't say what version of Archicad you are using).
Then do a Solid Element Operation with the wall as the target, the roof as the operator and use 'Subtraction with upward extrusion'.
The good thing about SEO is if you modify any of the elements the trim will adjust to suit.
Make sure your wall is higher than the highest point of the roo to close the side gap.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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