Here is a real long story to simply ask if some hamsters run hot...
When I bought a new water bottle the pet shop lady suggested I put a small glass bowl under the bottle that sits in the bedding just barely higher than the rest and then fill it with bedding so if the bottle leaked I could figure it out quickly and not have to throw out half of the substrate. For a few days my dwarf just sat on the rim of the bowl when he would drink but he has decided that bowl needed just a bit more bedding to make a nice place to nap.
At first I thought it was super cute but I've noticed that he mostly sleeps in areas that are high up and/or don't have enough bedding to make a nest. He seems to like laying on what I would think are cooler surfaces with just a bit of bath tissue but then covers himself with a bit of bedding.
His home doesn't get direct sunlight and doesn't have any kind of vents blowing it's way. He lives upstairs so it is a bit warmer during the day but still a comfy indoor temp.
He has a burrowing corner and a couple of hiding houses (he does sleep in one of those sometimes) I am going to add a shoebox house with the first cleaning as I provided hiding houses but not anything large enough for nest/hoard/potty all in one.
Is it possible my guy just runs hot or is he telling me to hurry up with the divided shoebox house?
Seems every question somehow becomes more about habitat than behavior.