By chief architect.
Build attic chief architect.
Launch chief architect and open the plan in which you need to manually draw in the gable wall.
Repeat this process for the opposing gable wall on this floor.
Certain conditions must be met before an attic truss can be built.
To manually add a gable wall.
To modify the area above the garage using the select objects tool click in the area or room that is above the garage on the 2nd floor to select it and click the open object edit button.
The structure should be sufficiently wide to allow for a loft and attic spaces the loft area must be on a living floor and have attic rooms on both sides separated by knee walls a flat ceiling in the loft area and a floor below steep enough roof pitch to provide appropriate ceiling height for the loft area.
It s easy to manually create attic walls to fill in gaps such as in gables where the program can t determine where one is needed or if you have turned off the automatic generation of attic walls.
You can build a cape cod or story and a half house by creating a new floor and rebuilding the roof.
With pro you can lock certain roof planes and perhaps leave auto roof on but it is best not to rely on that.
On the structure panel of the room specification dialog that opens lower the finished ceiling value to the height that you want the exterior.
If this is the case you will need to.