Create the dormer roof and join it to the main roof.
Revit roof dormer.
Use the modify sub elements button to select your newly placed points.
Select the wall type and constraints for a dormer that will be added to a roof.
This video demonstrates the following.
Use the join roof tool to join the dormer roof to the primary roof.
Revit 2021 inclined rafter joining roof rafter to dormer rafter paul building and architectural design autodesk beam inclined micrographics revit 2021 roof rafter when a dormer roof joins the main roof the rafters are not in line.
Select your flat roof press the modify sub elements button that appears.
After adding a dormer cut an opening for it through the roof.
Create the walls and roof elements that make up the dormer.
Create the roof opening and finish the dormer.
Add point or split line if better suited creates points at intersections place your new points as required.