How to copy an entire floor?

[ChiefXD]

Hai,
I would like to know if there is any option to copy/keep all the doors and windows of the floor below while adding/building a new floor.
While I build a new floor it just copies the external wall structure and excludes windows, doors interior walls etc.
In short what should I do to copy an entire floor to a new floor? Am I missing any option here or is it the way it is?

Thanks in advance.