Packed and Cramped
No Vacancy
The social aspect of crowding is that personal hygiene diminishes which will increase mortality rates because diseases will be more easily spread. The more people living and working in the same building jeopardizes structural integrity. With the increased weight that the people and their things exert on the building will cause very hazardous living conditions. The limited space will also cause a lack of housing, leaving people without shelter, making them desperate to support themselves. This would lead to ghettos, which could lead to increased crime rates.
http://prrn.mcgill.ca/research/papers/marshy.htm
http://prrn.mcgill.ca/research/papers/marshy.htm