Is it possible to have both a combi boiler and a conventional boiler?

Question:Is it possible to have both a combi boiler and a conventional boiler?

Would it be possible to have a combi boiler as your main water source and then a conventional boiler with a cylinder as a back-up water system should your combi boiler fail.

Doesn't matter about cost I just want to know 1) is it possible and 2) what are the implications.

(this would be on new build houses).

Thanks in advance.

Answers:
As long as they had similar operating parameters and you made the switchover manual, it could be done.