I've friends that won't come to visit me until at least May. They live in VT while I live about 75 miles away in NH. Why May? Because that's when it's safe for them to leave for an overnight trip. They heat exclusively with wood and don't dare stray too far from the house. If no one is there to feed the stoves, the plumbing will freeze, their plants will die, and they'll lose some food to freezing.
That's a tough way to live, but they are further out in the woods than I am. They don't get cars driving by their house. They get hikers. Of course they are off grid, so forget about having a couple space heaters as backup. They do have propane for their refrigerator, so they could install a propane heater for supplementary heat. Then again, they are probably afraid of using too much propane. I've reduced my propane usage from monthly deliveries to a delivery every two years. Winter deliveries were always a pain. The trail to the propane tank had to be kept shoveled out all winter long. My friends probably want to avoid the hassle of winter fuel deliveries.
It was worse in my grandfather's day. The woodstoves needed to get fed every few hours. Today, air tight woodstoves typically last 10 - 14 on a full load of good wood. Put some wood in before going to bed and there's still hot coals in the morning. My grandfather used to drink a big glass of water before going to bed. About 2 or 3 AM his bladder alarm would go off. He'd take care of business then load up the woodstove again. He thought oil fired central heat the best thing in the world.
I'm burning oil right now. I've got a nasty cold. It's -15 F outside. My wife is recovering from shoulder surgery. There's no one else around to feed the woodstove. Today I've got the luxury of burning oil, sitting inside drinking a hot coffee and typing on the computer. If I didn't have backup, I'd be out to the woodpile, cold or no cold.
I realize that oil fired central heat is probably a temporary thing. It might too expensive for me to use or we could have another oil shortage. As it is, I use about a 1/4 what I once did. Mostly just use it when I'm away or have a nasty cold. For the rest of this winter, it's a reasonable backup.
One good backup is to have an extended family living together. It's nice to have a few more strong backs around to keep the home fires burning. As more and more people double up, that'll be one upside to the situation. Although as I remember it, even though my grandfather had two strong sons, he was the one always getting up in the middle of the night to feed the stoves. We stubborn males take care of our families.
If I was going to leave my house for a month or more, I'd go through the trouble of winterizing the palace. Anything that would freeze I'd bring to my daughter's house -food, plants, beer, paint, etc. Then the well pump would be turned off and all the plumbing drained. It's a procedure that takes about half a day.
One solution is to live so simply that the place freezing up isn't a big deal. The hunting camp was never kept warm when nobody was there. There was no running water to freeze. It had an outhouse. We hauled water from the brook or snow melted on the woodstove. It's primitive, but there's not a lot to worry about. Just make sure all the water jugs are drained when leaving the place.
A lot of people around here use oil or propane for heat, but keep a woodstove hooked up in case. In the North Country, freezing is serious business. When spring comes, we feel we've earned it.