In a recent blog, Allison Bailes did a great job defining heat and explaining heat flow. It’s important to remember, though, that Allison Bailes lives in Atlanta. When the temperature drops to 6°F in Atlanta, the story makes national news. But when the temperature hits -20°F in Vermont, we just tell our kids to remember to wear a hat when they walk to school.
I think it’s fair to say that residents of the Peach State don’t fully understand the value of heat. Now, if you live in northern Vermont, it’s vitally important to pay attention to heat flow. When the temperature drops to -20°F or -30°F, heat quickly flows from certain objects to the outdoor air, and the results can be inconvenient.
If you live in a house that is connected to the electrical grid, the solutions to this undesired heat flow are fairly simple. All you have to do is buy a collection of inexpensive gadgets and plug them in. Once you’ve got heat tape for your plumbing pipes, a block heater for your truck, a battery charger, and a couple of hair dryers, you’re all set. (Well, more or less. Occasionally it’s also useful to have an arc welder and a small bulldozer. But that’s another story.)
What if you live in an off-grid house? Well, then you have to learn a few tricks.
Every incident described in the following dialogue actually happened. However, it’s possible that the events didn’t all happen on the same day; there may be some poetic license involved.
A cloudless day in January
Setting: The tiny lobby of the post office in Sheffield, Vermont, on a January day. Two customers are chatting.
Martin: Hi, Bill. What’s up?
Bill: It was 28 below at my house. What about your place?
Martin: Only 25 below. It’s always warmer on the hill.
Bill: Well, my car doors were frozen shut this morning. I couldn’t find my flat bar, so I had to use an ice scraper to pop the driver’s door. It took a while.
[Bill notices Martin’s cross-country boots and the ice on his mustache.]
Bill: Isn’t it a little cold to be skiing to the post office?
Martin: Truck wouldn’t start.
Bill: You should have brought your battery indoors last night.
Martin: I did. I put it on an orange sled and hauled it in. Left it on the shelf beside the wood stove all night.
Bill: And your truck still wouldn’t turn over?
Martin: No. I even tried the coals-in-the-lasagna-pan trick.
Bill: Huh? I don’t know that one.
Martin: That’s where you go out to your truck with a metal bucket full of hot coals from your wood stove, a lasagna pan, and a blue tarp. You pour the coals into the lasagna pan and put it under the truck’s oil pan. Then you put the tarp on your hood and wait 15 minutes.
Bill: Isn’t that how Fred burned up his truck?
Martin: Could be. Luckily, my truck didn’t catch fire. It just won’t start.
Bill: What about your old Subaru?
Martin: Well, the Subaru started. But I can’t move it because the truck is in the way.
Bill: Couldn’t you pull the truck with a come-along?
Martin: I thought of that. But I was cutting firewood yesterday up at my clearing and got my bar pinched. I used my chains and come-along to free my saw, and I left everything hanging from a branch in the woods. I didn’t feel like snowshoeing up there just to get my come-along.
Bill: Is your little tractor strong enough to pull your truck?
Martin: The fuel filters on the Kubota are clogged and the diesel is too thick.
Bill: Did you try pouring some kerosene in with the diesel?
Martin: I did, and that seemed to help. It almost started, but then the battery died.
Bill: Why don’t you charge the battery with your generator?
Martin: I forgot to bring the generator into the living room last night. The choke is frozen, and it won’t start. Otherwise I would have borrowed my neighbor’s Torpedo heater and built a few tents.
Bill: Well, at least it’s a sunny day. You’ll make a little electricity once the sun hits your solar panels.
Martin: The panels are iced up pretty bad from last week’s frozen rain. I can’t scrape them yet.
Bill: Try pouring some warm water on them.
Martin: That’s a terrible idea. It could crack the glass. Anyway, my water pipes are frozen.
Bill: Don’t you have a propane torch?
Martin: Yes, I went down to my cellar yesterday with the torch and I managed to get the water flowing, but then a different pipe froze — one of the ones behind the drywall. It’s a pipe that I usually thaw with a hair dryer. But I can’t get my generator started, so I can’t use the hair dryer.
Everything’s frozen solid. I had to put a big rubber basin of snow in the hen house, so the chickens can peck snow. It’s hard to give them enough water when it gets this cold.
Bill: Bob told me that the potatoes in his cellar froze.
Martin: That’s too bad. He should have covered them with hay.
Bill: He also ran out of dry firewood. I helped him move a cord of green wood into his living room. It steams up the windows, but at least the wood is beginning to dry out. While I was there, we swapped his propane tank. His driveway is too rough to plow, so I helped him pull in one of those 100-pound propane tanks on his toboggan.
Martin: Did you hear that Frank went away for the weekend, and he forgot to put antifreeze in his toilet? That’s the second time he’s cracked his toilet.
Bill: You’d think he would have learned after the first one. Are you going to be OK at your place with no car, no generator, and frozen pipes?
Martin: I’ll be fine. I’ll melt snow to make dinner, and I’ve got plenty of kerosene for the lamps in case my house batteries run low. Before I go to bed, I’ll bring the generator indoors. I should be able to get things going tomorrow.
Bill: It’s supposed to be 30 below tomorrow morning, so you should put an extra log on the stove before you go to bed.
Martin: Right. Don’t forget to leave your water dripping.
You can do better
Yes, we’re a bunch of hippies who live in leaky cabins. Learn from our mistakes! Remember, if your plumbing pipes or your potatoes are freezing, insulation won’t solve your problems. It’s all about air leakage, not insulation.
If you pay attention to airtightness when you build your home, and test it with a blower door, your plumbing pipes and potatoes will never freeze, even if you go away for the weekend.
Martin Holladay’s previous blog: “Open-Cell Spray Foam and Damp Roof Sheathing.”