I am at work and so tired (ds woke at 4.30 ffs!). I am not officially on work time - my working day is over and I am staying around to do some catching up as I am going out tonight with old friend so no time to go home first plus would disrupt dh doing dinner for kids etc. There are no empty offices. The staff room has armchairs but I would be embarrassed to be caught snoring by colleagues. Only room where I could feasibly have half hour power nap in on one of the very spacious toilet cubicles. There are plenty so I wouldn't be blocking anyone from using loo. They are pretty clean too.