Staying warm on a boat in Alaska

The author and his dog making tracks. (Photo: Patsy Urschel)
It’s 0700 naval time in early January 2021 – still 36 minutes to first light and an hour and 26 minutes before dawn – and it’s my turn to make coffee. I roll out from under the lovely warm blankets, encouraged by a muffled “thanks” from my wife, Patsy, and go upstairs in the dark. In the salon, I turn on the light and check the thermometers. It’s 11 degrees outside and 54 degrees inside. This is a major victory. Anything over 50 degrees in the salon first thing in the morning is a victory when you’re in Petersburg, Alaska, living on your boat in the winter.
It's not that Southeast Alaska is particularly cold. While I’m waiting for the kettle to fill at the sink, I check the Internet on my phone and see that it’s -30 in Fairbanks, but that’s inland. Southeast doesn’t get as cold because it’s mostly islands and the deep saltwater around us moderates the air temperature. Just up the hill from us at the airport it’s always 4 to 12 degrees colder than down here at sea level.
Our first line of defense against the cold is our on-board central heating system. We have a diesel furnace down in the engine room and a pump that circulates hot water through seven radiators on board. This hot water, filled with rust-inhibiting and boil-suppressing anti-freeze, also goes through a heat exchanger (basically, a radiator in reverse) which heats the fresh water for the sinks and showers. It’s called a hydronic system, and it works well, to a point. After that point, we have an electric space heater mounted in the salon and two portable space heaters, if we need them. I bolted a metal shelf to the wall over the salon heater and it’s turned out to be a good place to drop wet mittens.
Our second line of defense is insulation. Aside from what’s built into the boat, we cover the windows with a thin, clear, plastic film. Patsy puts two-sided tape around the frames, attaches the plastic, then shrinks it drum-tight with a blow dryer. The plastic traps the cold air against the glass, just like a storm window in a house. It makes a huge difference. Patsy does her plastic magic on the skylight, too.
Our third line of defense isn’t against the cold, exactly, but against the condensation that forms inside the boat when the warm air from our lungs or cooking or showers hits any exposed cold metal or un-plasticized glass. It gets incredibly wet in a lived-in steel boat in the winter. The walls sweat and the ceilings drip. The solution was a pair of dehumidifiers, each about the size and shape of a suitcase stood on end. There’s one in the pilot house and one in the master stateroom. They condense the water from the air into reservoirs in their base – and they work well, and we have to empty them every day or two. I’ve come to associate the pleasant tang of ozone with dry clothes and dry towels. The dehumidifiers run off our house circuit, but they draw enough amps that we only run them when we’re on shore power or when one of our generators is running.
We don’t have a dehumidifier in the salon, though, and this morning this was a problem. The relatively warm moist air inside condensed against the metal frame of the door, and last night it froze the door to the frame. Bella the dog came up and needed to be let out and I had to get the heat gun to open the door. Later today, I’ll smear silicon grease on the door jamb to keep it from freezing up tomorrow.
But now, I’ve ground the beans, applied the boiling water, filled two mugs, turned off the lights, and am headed back down to bed, trying not to spill the coffee in the dark. Patsy will be fully awake by now, halfway through her morning crossword puzzle. I’ve got a paper on glaciers I’ve been meaning to read for an expedition next season to Kenai Fjords.
— William Urschel