I like to model simple dropped/suspended ceilings with Beams for the tee-grids and the ceiling tiles as one Slab. Then use SEO to cut the tiles.
If I need to schedule how many of each size tile there is I can exploded the slab/tiles into morphs.
The way to generate the Reflected Ceiling Plan then is with the Floor Plan Cut Plane Settings of the RCP View.
This will depend on how you have your Stories set up and what Story you have the beams and slab displayed on. Personally, when I need to make a RCP for a suspended ceiling I add a Story to the model just that.
I model the fire sprinkler escutcheons, lights, smoke detectors, grills, vents... on that Story as well.
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