A few things have been covered and I will only touch upon these briefly. First I full time and have spent considerable amount of time, long periods, in single digit weather, without winterizing. My opinions are mine and not based on occasional use.
For long term use in cold conditions, I would encourage you to consider these three things;
1. Personal Safety
2. Cold Creep
3. Condensation
4. Personal Comfort
With your personal safety, caution should be exercised in any enclosed area when using any combustible fuel. Even though it is a large building, concentrations of deadly gases can and do build up. In your situation, they will begin to “pool.” While it might not be in concentrations, it can greatly impact your health, in many ways. My suggestion is to follow the advice of the previous comment and use the south side of the structure, or; increase or verify adequate venting is available. Open doors and evacuate the building on a daily basis and, use any combustible fuels sparingly. Use electrical appliances when possible, exclusively.
With Cold Creep, get it out of your head that you are going to keep your temperatures low. That is the first mistake many make in winter/cold conditions is allowing their core temperatures (of their habitat) to creep down. This can possibly damage electrical equipment, water equipment/supplies and foodstuffs. Btggraphix gave me a suggestions, years ago, and that was to use wireless thermometers in recessed areas, like my valve compartment, so as to monitor the temperatures in those areas. I just place the receiver on the wall near my kitchen sink, to monitor these temperature changes.
Some think that they can save money, or for other identified reason, by keeping temperatures low. This will cause very cold temperatures to slowly penetrate the camper, like a thermos bottle working backwards. Also, let’s be honest, many of us are not spring chickens and cold temperatures can and do impact our lives detrimentally and in an emotional way. Already you are going to be impacted by the lack of light (being in a building), shorter daylight, why subject yourself to lower temperatures? Keep your thermostat 70?F to 74?F. I do a lot of extreme measures with my full timing, but I draw the line at being cold.
You have mentioned that you have a dedicated electrical source, so use it! When I am in long term cold areas, I use a number of things, even when I don’t have electricity abundantly. For really cold temperatures, buy two small thermostat controlled electric heaters. Find locations at the lowest portion of your living area and set them there. Or one on the floor and one on a counter, facing where you are sitting. Just ensure they won’t tip over (even though manufacturers are not required to have a tip shut off), especially when pets are around. Also, you will have areas that are susceptible to damage from freezing, such as dump gates and water heaters. Most Lances have these valves inside cabinets and by placing a mechanic’s shop light (with a higher wattage bulb) in these locations, the heat that they generate will keep things from freezing. Make sure that the light is not touching or near anything that can burn or melt (plastic). Last season, I found a very small thermostat controlled electrical heater (Wal-Mart) and placed it in my Gate Valve enclosure area. By plugging the holes, by capping them and stuffing towels in them, you can keep things pretty warm, even in below zero temperatures. (Every few hours I run the generator to power my electrical heating appliances, when off the grid, as well with my furnace). Identify areas where your pipes are and keep those doors/cabinets open (cracked) to allow air circulation. Use this time to check for openings where the cold can creep in. Seal these areas off, by caulking, taping and using solid and batten insulation. I am a big believer of using a trouble light, at night, stuffed into areas to see where the light seeps out, revealing possible leak sources.
Condensation is a curse and hard to get rid of, once it starts getting out of hand. There are many things you can do to minimize this issue, in long term cold weather. Simple things, like; Cooking, boiling water for meals/pasta, heating sources and of course, breathing. For weekenders and short vacations, this is not as much as a problem, as it will be for you and has been for me.
Minimize using heating devices that dispense large volumes of water vapor, such as Wave Heaters. I love my Wave Heater, but with everything, there are compromises. The plus is when you can use the heat and then open the doors and windows, the next day, to literally dry out the camper. That is why most weekenders don’t experience heavy condensation. Try to capture this condensation every morning, by wicking out the window tracks and taking this water outside (towels or rail wicks) to dry. Try to do more cooking outside and refrain from bathing indoors. Yep, a quick hot shower outside can be invigorating, with a simple bucket and garden sprayer, suspended from the ceiling of the building filled from your water heater and mixed with some cold water (now you are seeing why some consider me an extreme boondocker). Be sure to check your cabinets and clothes. You might have to remove everything that can absorb moisture (clothes/foodstuffs) out of cabinets to keep them from growing mold, from the condensation (want to see pictures of a pair of dress shoes of mine that are covered in mold from last winter? I forgot them on the floor of my closet until I found them this summer.). I use sleeping bag stuff sacks to keep my clothes in (shirts, pants, underwear, socks on and on), in the winter time, so they are not stored in cabinets but on the bed or in the cab of the truck. That musty smell is horrible. Also, your mattress and anything touching the outside walls will become saturated with condensation and begin to get musty smelling. Be sure to check for this and take action when you find this. Yes, condensation can be an issue in the winter time, for RV campers. Some of the dehumidifiers do work and available on Amazon.
Personal comfort is important and a great combatant of; “Cabin Fever.” Dress in layers, get some light flannel gloves and a stocking cap, for wear while sleeping. Having a down comforter (Kohls) and a great cold weather sleeping bag, is a great resource as well (you will find the cab over area very cold). Keep your clothes clean and clean them often. It is common for people in these environments to experience “diaper rash” for not changing undergarments frequently. Eating well and comfort type foods ensure your own body heater works well. You are an experienced outdoors person and know this area better than most. Protein diet is important.
With the enclosed building, I would build a composting toilet or use an outside toilet to extend the black tank and dumping cycles.
One of the most important things, have fun and stay in contact with family and friends.
b
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