The information in this article applies to:
How can I create a flat roof in my Home Designer software?
Creating a flat roof in Home Designer can be accomplished in a variety of ways. In this article, the settings in the Build Roof dialog are be changed to approximate the look shown in the image above.
Only Home Designer Pro and Chief Architect versions of the software will allow you to select a roof plane and manually edit its pitch to be 0".
If only one part, or section, of the roof needs to be flat, do not set the pitch in the Build Roof dialog to be 1/4", instead, set the overall pitch of the majority of the structure in the Build Roof dialog and on an individual wall by wall basis adjust the desired pitches to be 1/4".