Take apart one section of roof: nothing in it (7)
I believe the answer is:
isolate
'take apart' is the definition.
(isolating is a kind of taking apart)
'one section of roof nothing in it' is the wordplay.
'one section of' becomes 'i' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'roof' becomes 'slate' (slate roof is a kind of roof).
'nothing' becomes 'O' (O resembles 0).
'in it' is an insertion indicator.
'slate' placed around 'o' is 'solate'.
'i'+'solate'='ISOLATE'
Can you help me to learn more?
(Other definitions for isolate that I've seen before include "split up" , "Place apart, away from others" , "Set apart from others" , "Ostracise" , "Seclude" .)