Hi Michael,
I live in Canada, just outside Montreal. We have very cold winters (-40ºC with the wind chill) and very hot, humid summers (+40ºC with the humidity). Gauge, our 18 month-old Flattie seems to prefer hard, cool surfaces as well, regardless of the season. He is definitely a house dog and if I sit on the floor at all Gauge is usually either half in my lap, or at the very least, lying next to me with his head in my lap. However, when we watch TV, he lies on the hardwood floor between the couch and the coffee table, or in the kitchen on the tiled floor. At night, he will either sleep on his dog bed (next to my side of the bed), or more often sleeps on the hardwood floor beside the bed. We have 2 dog beds in our room (we also have an 8 year-old Golden) and Gauge chooses the thinner, flatter bed if he does sleep on one and is usually only half on it.
I know he does sleep on our bed at least part of the time when we're out for the day, but I think this is partly because he likes to be near our Golden who spends the day on our bed.
I also find Gauge has a hard time handling the heat and tends to get overheated fairly easily so we have to make sure not to run him too hard in warmer weather and to have lots of water around. In the winter, he loves to flop down and lie in the snow, often stretched out so that his full underside is against the snow.
So, my Flattie prefers the cold as well. Maybe not to the level that you're describing, but if you've found what makes your guy happy, then I would stick with that and not worry about what the breed tendancy is.
Enjoy!
Melissa