Incident radiation showing patchy results with multi layer geometry

hi all, im running an analysis on diff orientations for a house model. so im running into an issue with IncidentRadiation in GH. My building’s split across layers in rhino (roof, out wall, floor, inner walls), and when i run the analysis i get the result attached below of multiple geometries instead of one common.

ive tried merging all the layer geometries into one via a merge component + flatten before feeding into incident radiation, but it’s still doing the same thing.Any ideas welcome. my gh file

@nishxrhino if you hide the parent geometry it should clear up
best
-trevor