Fawlty in charge of a building in Rome (8)
I believe the answer is:
basilica
'building in rome' is the definition.
(St. Peter's Basilica in the Vatican)
'fawlty in charge of a' is the wordplay.
'fawlty' becomes 'Basil' (Basil Fawlty of the sitcom Fawlty Towers).
'in charge of' becomes 'ic'.
'basil'+'ic'+'a'='BASILICA'
(Other definitions for basilica that I've seen before include "Roman-style church" , "Magnificent church" , "Roman hall; church" , "Church or cathedral of high rank" , "Romanesque church" .)