Inside a loft, around model (5)
I believe the answer is:
ideal
'model' is the definition.
(I know that ideal is a type of model)
'inside a loft around' is the wordplay.
'around' indicates the answer is hidden within the clue.
'IDEAL' is hidden within 'inside a loft'.
(Other definitions for ideal that I've seen before include "Dream" , "An - - Husband (Wilde)" , "that can't be bettered?" , "Best possible" , "Perfect but not likely to become a reality" .)