what if a chimney is not used, but cannot be removed?

Hello! I am a (volunteer) trustee of a condo association. Our building is a historic school, originally built 1898. It was converted to condos in 1987. Climate zone 5A (Massachusetts).Our… Hello! I am a (volunteer) trustee of a condo association. Our building is a historic school, originally built 1898. It was converted to condos in 1987. Climate zone 5A (Massachusetts).Our…Read MoreGreenBuildingAdvisor