At TU Wien every room is identified by a room code that consists of three parts, that identify:

  1. part of the building
  2. floor of the building
  3. number of the room

So for example DEZE08 means building part DE (Treitlstraße) ZE (Zwischenetage), room 12 (FSInf-Kitchen). Unfortunately the TISS calendar (and most institutes) use room names instead, which while easier to pronounce are often ambiguous and don't necessarily indicate the location of the room.

TU Wien has its own working maps service nowadays: https://maps.tuwien.ac.at/?q=DEZE12