Householders' overheads (5)
I believe the answer is:
'householders' overheads' is the definition.
The answer and definition can be both man-made objects as well as being plural nouns.
Perhaps you can see a link between them that I don't see?
This is the entire clue.
Can you help me to learn more?
(Other definitions for roofs that I've seen before include "Protective coverings for buildings" , "Tops of buildings" .)