I have an ~ 80 year old house, with a 1 pipe steam heating system.
This is our 2nd winter in it.

There is one room that we do not use much upstairs (4 rooms upstairs, ~
1,100 sqft total. Is it worth turning off this radiator, or would the
savings be negligible?

Looking at it briefly it seems as if it obviously would save $, but in
reality the boiler runs for ~ 15 minutes before it starts feeding steam
through the house, and then say another 10 minutes while steam is
delivered. By closing off one of the 10 radiators in the house, I
don't think the boiler runs that much less (I haven't tried timing it).

This is a room we keep open, becuase we want it 60 F, so it is not as
if we are shutting it off from the rest of the house, in which case a
savings would be obvious.

Any thoughts are appreciated.

Thanks,

Chris