Loft to Temperature ratio?

[Living the Highlife]

Hello fellows,

It has come to my attention that the majority of the DIYers here have different levels of loft in relation to temperature and where they are located, but is there a general rule of thumb for loft in relation to how cold you want it down to? Just curious cause I'm contemplating multiple things for my first DIY under quilt.

1. Karo Step pattern or Normal baffle pattern
2. Down and fill power
3. How big am I making this thing (I'm 6'2")

I'm overall trying to get this down to 0 degrees and the consensus is anywhere from 3 to 3.5" of loft.

I figure I would let this one fly considering it's getting colder outside. (at least in VA anyway!)