Roofs can be at any height you like within a storey.
You then have Floor Plan Display options to set if you want to see them on the storey/s above or below.
So place you roof in what you would consider to be their home storey, and set the height and FPD options as you require.
As for the new storey, I like the KISS (Keep It Simple Stupid) rule.
One storey for each floor level.
Some like to add storeys for foundation walls, ceilings, roofs, etc., but I think this just over-complicates things.
It may mean that you need a few more layers to turn things on or off however.
You have to find the way that works for you the best.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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