I found a work around to getting the framing details to show on level 0 for the under deck storage area:
Edited the wall type
Created a copy of Siding-6 (called it Siding-6, UnderDeck)
Deleted all the layers except the Fir Framing
This resulted in attached view. However, this is far from ideal as i'll have to keep switching the wall type depending on what i'm trying to do (e.g. produce material list).
I'm still very interested in how to get the framing view on level 0, i.e. foundation level wherever siding-6 or other wall type which has timber framing is being used.
Thanks.