I will join your vent though our house is warmer than 64. I just can't go that low but I'm still freezing at 68. I'm wearing a fleece & unfortunately, am usually cold most of the time - I blame my thyroid. Though our bills aren't bad - gas/water is $99 & electric is $73 on budget bill & has been about that for 2 yrs. 2000 sq ft above ground.
How much insulation did you have to add? I wondered about that when I saw it in an ad this week. Our upstairs is freezing, even more so than the main level. I have flannel sheets on all the beds but it'd be nice to have it a little warmer.
Ugh, I'm not at all ready to hibernate for the winter yet!