The dormer is defined on the roof with the dormer command. To define the dormer, the roof must first be defined.
Location of Dormer Command
You can access it under the heading of the Ribbon menu, Home tab, Roof .
Click the Dormer icon in the ribbon menu .
The dormer toolbar will open and the cursor will change to the dormer type that can be selected in the Dormer Settings dialog.
Place the cursor on the roof object. You can use the coordinate system to find the proper position.
When you click the left mouse button, an dormer will be formed.
Creating the dormer preview and determining where to create it
Creating dormer by clicking the left mouse button