This video will show you how to do it automat.
Revit roof unwanted valley.
To create a dormer model required walls and additional roof.
You need to create the bay window roof separately.
Then follow these 2 steps.
9 join roofs add opening to create dormer.
I believe this tools are not design for this purpose.
Use it to extend the dormer roof to the main roof.
This is not a revit problem but a roof design issue.
You have to make the lower roof wider grow to the right to raise the ridge to eliminate the valley or you need to modify your porch roof moving it left to ellimnate the unwanted valley.
I did on my model but i am not very happy with the results.
I need to create that to be able to get in schedule lenght of it.
This tool is located in the modify tab.
Tutorial on roof construction modeling in revit.
For creating complex roof it might be easier if you create separate roof then use join roof tool to join them later.
Is there any other way of creating roof valley.
Use join unjoin roof tool.
But i m not really sure if this is a best practice.
This is the easiest way to do it.
Using shape editing tools.
See hd version of video tutorial here.
Creating complex sloping roofs in revit 2014 roof junctions controlling roof slopes and levels.