Simple building discarded (4)
I believe the answer is:
shed
This clue is a double definition.
'simple building' is the first definition.
(I've seen this before)
'discarded' is the second definition.
(I've seen this before)
(Other definitions for shed that I've seen before include "Lose as trees do leaves" , "Abandoned" , "Threw off the hut" , "Removed in garden hut" , "Kind of hut - discard it" .)