Take the lift down to -2

[Bobette]

I'm a native English speaker and I'd like to know how you say that "-2" in "Take the lift down to -2" : do you say "minus two" or "level 2 below ground floor" or ???
Thanks a lot !

[Ouisch]

I've heard a couple of different phraseologies used...."lower level 2", or "sub-basement", for example.