Ashtons room would be alot less than 20 degrees. Maybe around 14 in the middle of the night, and I say 14 cause that is what our lounge-room will get down too if we don't have the heater on, and our lounge-room cops the afternoon sun (if any). We dont' have central heating and only have 1 small column heater that does what ever room we are in at the time, usually the lounge, and it is turned off at night.

To compensate he goes to bed in his sleeping bag for extra warmth.

Love