Good building design goes beyond structure. Focusing on things like ventilation...

https://miasimpressiveperspective.quantlynix.com/posts/upper-floor-tenement-with-no-lift-what-options-exist-as-mobility-changes

Good building design goes beyond structure. Focusing on things like ventilation and airtightness retrofits can make homes healthier and more comfortable. Proper airflow keeps CO2 and humidity in check, while airtightness cuts drafts and energy loss