The service tower is accessed at gallery level from inside the building, and through the building itself at ground level. It cannot be entered directly from the street. It contains a lift shaft and also serves as a ventilation shaft for the entire building. For the really adventurous, there are a couple of chairs perched suspended over the pavement. These tend to remain empty during daylight hours. It is only later, when punters are stocked up with some Dutch courage, that the more adventurous ones venture out here.
Side note: The Irish and Welsh flags can just be seen on the cirved glass wall in front of the two chairs. These were a hang-over from the European Championships qualifier match which had been played in Croke Park the previous Saturday.