The answer is "yes, but only if it is a version that they know about and can detect"
There are a few considerations to the OP's question. There are different levels or aspects:
1. Computing facility destroyed by fire, earthquake, flood, terrorism etc. For this kind of eventuality you would probably go for an offsite backup facility.
2. Minor problems such as power or a localised fire or flood just affecting IT. Here you might look at portable buildings and equipment brought onto site.........not so easy in a city centre?
3. Business continuity. This is just being able to run the business in the event of a problem. You need to include all the departments in this one, as the people need somewhere to work, to produce, to distribute etc. Here you might look at subsidiaries and different branches/sites.
With business continuity you need to look at just how critical your applications and access really are.
Don't forget UPS and emergency generator facilities with this one.;)