Speaker's closing upper house? (7)
I believe the answer is:
ceiling
'upper house?' is the definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Maybe you can see a link between them that I can't see?
'speaker's closing' is the wordplay.
'speaker's' shows a homophone (sound like).
'closing' becomes 'sealing' (sealing is a kind of closing).
'sealing' is a homophone of 'CEILING'.
Can you help me to learn more?
(Other definitions for ceiling that I've seen before include "likely to get plastered" , "Overhead surface" , "Room's upper surface" , "upper limit on wages" .)