I believe these are simply ThreeJS artefacts - annoying, yet benign. This would not (or should not) add additional vertices to the OSM. Are you seeing them pop up with other renderers (e.g. SketchUp plugin)? Below are OpenStudio App vs SketchUp plugin views of the US DOE SmallOffice Benchmark.

Are you otherwise noticing related warnings/errors in eplusout.err?