Building workers dividing opinion (8)
I believe the answer is:
tenement
'building' is the definition.
(I know that tenement is a type of apartment building)
'workers dividing opinion' is the wordplay.
'workers' becomes 'men' (men can mean staff or employees).
'dividing' is an insertion indicator (inserted letters divide the word).
'opinion' becomes 'tenet' (I've seen this in another clue).
'men' inserted into 'tenet' is 'TENEMENT'.
(Other definitions for tenement that I've seen before include "Holding" , "Run-down apartment house" , "Permanent property held by tenant" , "Rundown house with many occupants" , "Building containing several dwellings" .)