Engaged in renovation or doing nothing about it (9)
I believe the answer is:
restoring
'doing nothing about it' is the definition.
I can't tell whether this definition defines the answer.
'engaged in renovation or' is the wordplay.
'engaged in' is an insertion indicator.
'renovation' becomes 'resting' (I can't explain this - if you can you should give a lot more credence to this answer).
'resting' placed around 'or' is 'RESTORING'.
Can you help me to learn more?
(Other definitions for restoring that I've seen before include "Returning to the original state" , "Bringing back to former state" .)