It depends on what kind of English you're speaking, but you're right. If you think: ground floor, first floor etc, "niende etasje" is indeed the eigth floor. I am not sure why Norway and Sweden follow the East-Asian/North-American scheme for numbering, rather than the European scheme as Denmark does.
Hmmm. I guess it makes sense. Definitely needs to be clearly marked as such - I got a 'correct' for saying aattende when I meant niende (just being clumsy/stupid) and had no idea about the floor thing, was just translating the number. Maybe just needs a clearer marker saying somethign about the different floor systems >.<
I had no idea that the US and UK counted it differently. For instance, in my country the ninth floor would be the ninth floor after ground floor (0th floor). Meaning that we don't count ground floor as a floor, we start counting after it. I think this could lead to funny mistakes if someone told me to meet them at 9th floor in the US. I'm confused now lol
How does the floor counting work in Norway then?
I think (in this case) "sj" acts as 1 letter (with a long a) and I think "skj" does not occur in a position where it would matter.
Edit: I'm not sure anymore. The "a" definitely sounds longer than the "e" before it but, maybe I'm wrong. I can't decide weather the consonant is long. I would have said it isn't but now that I'm concentrating on it, I'm not sure what I hear.