Plastered if I cement inside building (7)
I believe the answer is:
edifice
'building' is the definition.
('edifice' can be a synonym of 'building')
'plastered if i cement inside' is the wordplay.
'inside' indicates a hidden word.
'EDIFICE' can be found hidden inside 'plastered if i cement'.
(Other definitions for edifice that I've seen before include "Construction" , "erection" , "Impressive building" , "Permanent building" , "'Large, imposing building (7)'" .)