Model your larger roof if that works and then select it and use the pet palette to subtract the area you don't want rather than SEO.
Make sure you activate the pet palate on the perimeter of the roof and not the pivot line.
If you choose the pivot line you will completely change the geometry of the roof.
Otherwise model just the part you want with single roof planes.
Sometimes single roof planes are easier to work with than the multi-plane roof.
And remember you can always model a multi-plane roof and then split it into single roof planes.
Barry.
One of the forum moderators.
Versions 6.5 to 27
i7-10700 @ 2.9Ghz, 32GB ram, GeForce RTX 2060 (6GB), Windows 10
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