Exchanging very small talk, maintaining historic buildings (12)
I believe the answer is:
conservation
If this is the answer I cannot explain how the clue works.
Can you help me to learn more?
(Other definitions for conservation that I've seen before include "good husbandry" , "management of natural resources" , "Preservation (of wildlife)" , "Care and maintenance of the environment" , "Careful use (of a resource)" .)