The BCP should also spell out a plan for setting up operations at an alternative location if the building is destroyed or rendered unusable by a disaster.
Best practice is to have ready access to an empty facility that you can move into; a more practical (less expensive) alternative would be to move your operations to a branch office if you have more than one physical site.
Any good business continuity plan will address restoration of your company's important digital data if it is destroyed.
Too many organizations meticulously make backups of everything and then store those backups in the server room.
Providing full electrical power to a building with a generator can cost much more than using the power grid, so the BCP should discuss in what situations it's better to close down operations and send everyone home rather than run on generator power, and it should define who has the authority to make that decision.
If your company's phones and/or Internet connection are down, how will you keep in touch with customers, employees who are off-site, contact emergency services, etc.?
Just as important, key personnel should know where it's stored and have the keys, passwords, etc., to be able to restore it to get users back to a productive state as soon as possible.
Many types of physical disasters can result in a loss of electrical power, or a power outage can, itself, be the disaster.
A cyberterrorism attack might bring down your network but not affect the functionality of the hardware or your personnel.
A bombing may destroy both human life and network components.