Door
Doors are used to enter and exit buildings. Zombie cannot open doors, but they can bash through them, breaking the door permanently.
A door can be barricaded, giving it an additional 30 health.
There is currently only one type of door, although more types will probably be added with future updates.
Weak Wooden Door
The weak wooden door is a normal regular door. It is the main door type of buildings in the suburbs. It has 5 Health.