Show houses occasionally feel vulgar (10)
I believe the answer is:
indelicate
'vulgar' is the definition.
(thesaurus)
'show houses occasionally feel' is the wordplay.
'show' becomes 'indicate' ('indicate' can be a synonym of 'show'**).
'houses' is an insertion indicator.
'occasionally' means one should take alternating letters.
The alternating letters of 'feel' are 'el'.
'indicate' placed around 'el' is 'INDELICATE'.
(Other definitions for indelicate that I've seen before include "Saucy" , "lacking taste" , "Coarse" , "Practised (a play)" , "Rather rude" .)