Building stocked remote safety device (5,8)
I believe the answer is:
smoke detector
'safety device' is the definition.
(I've seen this before)
'building stocked remote' is the wordplay.
'building' indicates an anagram.
'stocked'+'remote'='stockedremote'
'stockedremote' is an anagram of 'SMOKE DETECTOR'.
(Other definitions for smoke detector that I've seen before include "Kitchen safety device" , "It warns of fire" , "Precaution against fire" , "Home safety device" , "Building safety device" .)