ZRH: inside terminals and lounges
 

I travel to ZRH at least once per year, but neither in Jan nor in transit. So, I haven't had to stay in the terminal for an extended period of time in winter.

Yet, in a few days, I will have to be in a transit lounge(s) (will try out the new Primeclass lounge) for several hours. So, my question is: if this is the case, then do I need to bundle up? My origin/destination isn't really cold (20 C or low 70s F) and thus I would like to avoid bringing too much clothing.

I was last in Zurich in early Jun 2018. The heating was very strong at least (almost too strong, for Americans).

Thanks for your insights!

I don't recall ever having to exit the building while transiting ZRH in the past, but I might not have had representative experience in prior trips. One place where you can go outside while remaining airside is one of the lounges that has terrace seating. But, if you get cold, you can always just sit inside.