as ur local architect i could give 100 answers to this ask. but here is a social housing project i really love.
the most sustainable building is one that already exists, building anything new is inherently bad for the environment (buildings make up 40% of global emissions!).
rather than propose an entirely new building for this public housing project, lacaton & vassal proposed essentially renovating the existing and extending the building outward in the front by adding a layer of these kinda indoor/outdoor living spaces. i love this as a low cost solution that not only raises the economic value of these apartments but also is an incredibly valuable space for the well being of the tenants.
pic of the diagram showing before and after but def encourage taking a look at the pics in the link!