Habitual drinker, extremely plump, interrupting roof worker? (7)
I believe the answer is:
tippler
'habitual drinker' is the definition.
(I've seen this before)
'extremely plump interrupting roof worker?' is the wordplay.
'extremely' means to remove the middle letters (only the extremes of the word are used).
'interrupting' indicates putting letters inside.
'roof worker?' becomes 'tiler' (I've seen this in another clue).
'plump' with its centre removed is 'pp'.
'pp' placed into 'tiler' is 'TIPPLER'.
(Other definitions for tippler that I've seen before include "One habitually drinking" , "Heavy drinker" , "Boozer" , "Person who drinks constantly in small amounts" , "Imbiber" .)