communal staircase

[Michela]

Hi all
I am quite new to ies-ve and am currently modelling a flat that is accessed
by a communal staircase. In order to take into account the fact that the
staircase is not an heated space I have modelled that space as a room (not
as an adjacency) and applied to that one a thermal template with no heating
system.
I have modelled it as a single space that runs vertically through the whole
building (treated as adjacency to my flat) with floors at each level and a
hole in the middle of them.
Is that correct? Should I instead treat that space as an adjacency and is
there a way in this case to consider that one an unheated adjacency?
Thanks!
Michela