I tried this now. Deleted the roof. Copied the bottom floor walls again and tried to add the roof and didn't work.
Then First changed it to a roof on the root template. And it still didn't allow me to fill up the middle. the "type" section was all this time still impossible to change.
I then though it may be a problem with copying the walls cnd changing it to roof. So I went to an empty part and just placed down a roof. Made a square roof with the edit wall tool, but even that roof I am unable to fill.
I'll keep it as is for now. does make it easier to fill the building with things if it's open. Hope I can get it working in the future. If anyone has any idea I am all ears!
Thanks.
