Where there's a roof over one's head (5)
I believe the answer is:
attic
'head' is the definition.
(attic is a kind of head)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for attic that I've seen before include "where high-ups are found?" , "Loft room" , "Greek - upper room" , "Athenian Greek" , "Area at the top of the house" .)