Release on the house (4)
I believe the answer is:
free
This clue is a double definition.
'release' is the first definition.
(I know that release can be written as free)
'on the house' is the second definition.
(something on the house is given away free)
(Other definitions for free that I've seen before include "Costing nothing" , "Type of tenure" , "Available - for love" , "unemployed" , "unlike battery hens" .)