Established procedure at home (7)
I believe the answer is:
habitat
'home' is the definition.
(I know that home can be written as habitat)
'established procedure at' is the wordplay.
'established procedure' becomes 'habit'.
'habit'+'at'='HABITAT'
(Other definitions for habitat that I've seen before include "Natural home and surroundings" , "Animal's natural home" , "Natural home of a plant or animal" , "Natural environment, plant or animal" , "Territory" .)