Surface matching in OpenStudio looks for duplicate surfaces (with opposite face normals) in adjacent zones or spaces (zones in legacy, spaces in newer OpenStudio). The new OpenStudio that works with OSM files also has an intersect button in the surface matching dialog. This will find overlapping coplanar surfaces and split them to prepare it for surface matching. You then run surface matching as a second step. If you are using the legacy version of OpenStudio then you can use a native SketchUp feature to accomplish this. Select surfaces that are not matching, then right click and choose "intersect surface with model" or something similar to that. After you intersect in all problem surfaces ,re-run match surfaces.
David
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David Goldwasser
OpenStudio developer
david.goldwasser@xxxxxxxx