Green facilities can be defined as facilities that have net environmental benefits over their lifecycles compared to conventional construction, including benefits for occupants of their indoor environments as well as the natural environment.

Retrofitting refers to changing the system or structure of a building after it has been initially constructed and occupied. Retrofit renovations have the potential to enhance hospital building functionality while also enhancing the amenities available to patients and care providers.

Biophilic design aims to reconnect people with nature in modern spaces and It builds on the idea that humans have evolved in close connection with the natural world and this bond still plays a key role in human physical and mental well-being.