Do you have the ACCESSORIES add-on loaded?
If not go to your HELP menu > Downloads and make your way through to the add-ons.
Once you have this loaded you will have a Roof Accessory add-on that works with single plane roofs (not with multi-plane).
This accessory will automatically match the geometry of your roof and will adjust as you alter the roof.
Barry.
One of the forum moderators.
Versions 6.5 to 27
i7-10700 @ 2.9Ghz, 32GB ram, GeForce RTX 2060 (6GB), Windows 10
Lenovo Thinkpad - i7-1270P 2.20 GHz, 32GB RAM, Nvidia T550, Windows 11