After Henry goes, raises part of roof (5)
I believe the answer is:
eaves
'part of roof' is the definition.
('eaves' is part of 'roof')
I don't understand the remainder of the clue.
(Other definitions for eaves that I've seen before include "what might constitute a hangover?" , "Projecting edge of a roof" , "Part of a building's roof that overhangs the walls" , "Overhanging roof edges" , "Overhang at edge of a roof" .)