Since it took me a little while to find the special roof window library, I am also linking it here in case anyone finds it useful.
https://sourceforge.net/p/sweethome3d/plug-ins/40/#b551

@Keet or @Dorin, perhaps the link could be added somehow more prominently somewhere, e.g. at the Plugins Page or ...

Nevermind, found this from Dorin, that should do the deal https://sweethome3d.com/support/forum/v ... ,240#61532

Hi Keet,

Thanks for the quick input. I had experimented with the roof generator but did not get the hang of it. I have tried again and get better results now. What I have not yet figured out is whether I can create the roof from one room, or whether I would need to piece it together from multiple ...

Update:

I have found one half of the solution. It seems that the levels were off and that the upper floor's floor was lower than the ceiling thereby masking the display of the ceiling. Re-aligning the floor elevation, thickness, and height has solved the issue for level ceilings. Keet's guide at ...

Hi,

I am currently having an issue with the ceiling feature in only one project and am looking for suggestions what to do next.

I have worked with the ceiling feature of rooms both sloped and standard and they have worked well. In my current project, I missed to check for this at an early stage ...