Question-and-Answer Resource for the Building Energy Modeling Community
 | 1 | initial version |
OpenStudio doesn't let you switch a sub-surface to a base surface, you can only switch a base surface to other kinds of base surfaces, or a sub-surface to other kinds of sub-surfaces.
When you delete lines in SketchUp it automatically merges the two surfaces, and it isn't always predictable which surfaces is left. The easiest solution to your problem is to select the surface in the SketchUp plugin, and delete it. Then re-draw using the line tool one of the edges where the surface was. It will re-draw a new face and OpenStudio should properly classify it
