Then follow these 2 steps.
Revit roof unwanted valley.
Edit the roof sketch double click the roof or select the roof and click modify roofs tabmode panel edit footprint or edit profile.
Use it to extend the dormer roof to the main roof.
Creating complex sloping roofs in revit 2014 roof junctions controlling roof slopes and levels.
I need to create that to be able to get in schedule lenght of it.
Is there any other way of creating roof valley.
Tutorial on roof construction modeling in revit.
After creating a roof you can change its shape or overhang cut openings or align ridges.
Use join unjoin roof tool.
See hd version of video tutorial here.
To create a dormer model required walls and additional roof.
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.
I did on my model but i am not very happy with the results.
Get these project files and all advanced 1h courses.