I don't, and most don't either: there is no room. We have hot pipes through which hot water is pumped. At best, the high-rise itself has a hot water heater, but

I don't, and most don't either: there is no room. We have hot pipes through which hot water is pumped. At best, the high-rise itself has a hot water heater, but even that probably only holds a few hours worth of water. Serious storage is only there at the neighborhood level.