Posh new patio, heaven (6)
I believe the answer is:
utopia
'heaven' is the definition.
(a utopia is a perfect place)
'posh new patio' is the wordplay.
'posh' becomes 'u' (abbreviation for upper-class - opposite to non-U).
'new' is an anagram indicator.
'patio' anagrammed gives 'topia'.
'u'+'topia'='UTOPIA'
(Other definitions for utopia that I've seen before include "Sir Thomas More's perfect country" , "Idealised place" , "Sir Thomas Moore's perfect society" , "work in Latin" , "Literally nowhere" .)