“Extra insulation, sealing cracks, etc. I did that.”
Ditto, but the house is 52 years old. There is only so much you can do. Also, added a Harman pellet stove insert to help use less heating oil in the winter.
It is 77 sunny today. Then back in the 50’s for the next five days with rain. The pellet stove will be burning again.
I'm in a similar situation. Though my house is not quite 30 years old, the next steps to improving the house would be replacing the windows with double or triple paned windows, and removing the sheetrock so I install real insulation in the walls instead of having just "builder grade" insulation. Those improvements simply are not feasible.
Tell me about pellets. Are they readily available? Is it the kind of energy market that's overly regulated and, thus, has limited supply, or is it easy to find from anyone with spare wood (i.e. saw mill's byproduct)? That seems very efficient if it's as easy to obtain as I just made it out to be.