The sort of expert to bring the house down (10)
I believe the answer is:
demolition
'down' is the definition.
The answer and definition can be both acts as well as being singular nouns.
Perhaps you can see an association between them that I can't see?
I don't understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for demolition that I've seen before include "Licking" , "defeat" , "explosion" , "destructive action" , "ruin" .)