I did on my model but i am not very happy with the results.
Revit roof unwanted valley.
Use join unjoin roof tool.
Hello i read here and there that the best way is to create roof valley with roof fascia.
Edit the roof sketch double click the roof or select the roof and click modify roofs tabmode panel edit footprint or edit profile.
If you want to change the position of the roof use the properties palette to edit the base level and offset properties to change the position.
Use it to extend the dormer roof to the main roof.
This tool is located in the modify tab.
After creating a roof you can change its shape or overhang cut openings or align ridges.
To create a dormer model required walls and additional roof.
I need to create that to be able to get in schedule lenght of it.
9 join roofs add opening to create dormer.
See hd version of video tutorial here.
Tutorial on roof construction modeling in revit.
Is there any other way of creating roof valley.