This tool is located in the modify tab.
How to join double pitch roof in revit.
Then select the face of the roof you want to join in to and then.
You can use height or slope value specify the method and the constraint values from properties palette.
Groin vaults for your single groin needs 3 create a flat roof no edges defining slope then use the roof shape editing tools add split line set heights see attached revit file.
Select an edge of the roof that you want to join and then select the wall or roof to which you want to join the roof.
2 roof by extrusion needs to be cut and use multiple pieces as it turns corners this link explains a similar process fear and loathing in a cad vs.
Then follow these 2 steps.
Using shape editing tools.
Http pbl stanford edu how to attach walls to roof objects in revit.
Revit roof slope can seem complicated at first glance but by learning a few critical features you can create any roof shape you desire.
Whether you want a double gable roof with 6 pyramid shaped dormers or a simple gambrel roof the basics remain the same.
If necessary use the viewcube to spin the design to facilitate selecting the wall or roof edges.
To create a dormer model required walls and additional roof.
We want to join this face to the roof.
Use it to extend the dormer roof to the main roof.
Click modify tab geometry panel join unjoin roof.
With the join unjoin roof tool selected you need to click on the line of the roof which is on the face of what you want to join to the other roof.
Use join unjoin roof tool.
9 join roofs add opening to create dormer.