Awful house in conversion (7)
I believe the answer is:
heinous
'awful' is the definition.
(I've seen this before)
'house in conversion' is the wordplay.
'conversion' indicates an anagram.
'house'+'in'='housein'
'housein' anagrammed gives 'HEINOUS'.
(Other definitions for heinous that I've seen before include "Shocking (offence)" , "Atrocious" , "Shockingly wicked" , "Iniquitous" , "Revolting" .)