Have a poorly insulated block house. It's over a crawl space, except for the converted sunroom, which is large and over a slab. I keep it at 42' in the winter, and have to heat it up and keep it heated with the insert, which is a challenge. Once warm, I can keep the place warm if I'm tending the stove religiously. But I'll drop 10' overnight on a coldish for here (low 20's) night, even on a fresh 11p reload (about 4 hours of good heat output). Found a place that had no ceiling insulation using my seek camera (cool!). Most of the rest of the ceiling had 6" of batt/cellulose (rock wool?) insulation. I blew enough fiberglass up there to get it to R-40 - 50 range. In the sunroom, I couldn't access the attic directly. Removed some A/C ducts and blew in as much as I could. $500 investment (which will likely never pay off). However, I'm hoping that it makes the house easier to heat and more comfortable. I have an ecobee t-stat with all of last year's indoor v outdoor temps, so I should be able to get a pretty objective idea of whether or not this makes a difference in heat retention, esp at night. This makes the geek in me excited. Wondering if anyone here has done the same?