“…Studies published in recent literature have started investigating, in a systematic way, the overall quality of built environment [ 29 , 30 ] and living spaces, revealing that the absence of accessible outdoor space from the house (e.g., garden, terrace) contributed to concerning levels of psychological and behavioral symptomatology [ 31 ], confirming that housing environments could be associated with the mental health and wellbeing of residents [ 32 , 33 , 34 , 35 , 36 ]. While mental illnesses can be investigated through structured and validated scales, housing quality is mainly assessed in terms of occupants’ perception, due to the complexity of surveying a high number of different apartments and the low psychometric reliability of existing tools [ 37 , 38 , 39 , 40 , 41 ].…”