Building the Ultimate 4-Season Off-Grid Camper: An OREC Board Member Engineer’s Guide to Zero-Thermal-Bridging Travel

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For 5 years I owned a Pleasureway Camper van built in Saskatoon. I enjoyed traveling in that van with two exceptions: that it was not built to go on bad roads due to it having little clearance and rear wheel drive, and that the fresh water, gray water, and black water tanks were all mounted outside, meaning they froze when it got below 0 °C.

I wanted to go further out, which meant a 4x4 truck with higher suspension. Thus the need for a truck camper. This unit would also need to have all the water on the inside so it would not freeze.

I spent about 6 months reviewing campers online and speaking to sales people. I decided the best way to really compare them was to visit the manufacturers and see for myself. I had a clear idea of what I wanted:

• Fits on an F-150 with an 8 ft bed

• Weight: max payload for ~2,700 lbs

• 4 season use: I wanted a camper I can use in 4 seasons without the problems I have had with a camper van where water tanks freeze in below-zero temperatures

• Able to camp off grid 3–5 days with no services (water, electricity, dumping)

• Load and unload from truck without too many connections

• Portable: move to another truck with an 8 ft bed with little issue (new EV truck, selling camper, etc.)

• Lithium-ion batteries, solar panels, and induction cooktop (no carrying propane)

  
  

In the fall of 2024, I went on a road trip to visit 7 different manufacturers of campers. I traveled all the way to Colorado and back meeting and discussing with camper designers. All insisted they could be carried by an F-150, although several were 3,000 lbs and up. Some were pop-up campers, some fiberglass, some aluminum, and some framed with wood. The issue with many of these materials is that they do not work well in cold situations due to interior condensation (inducing mold and rotting wood), had thermal bridges from the aluminum, or just were not insulated enough to be comfortable in below-zero temperatures.

After I got home I was a little disheartened. I also was not very excited about buying things from the US as Trump had been elected while I was on my trip. Again going back to the internet, I found a company in Vancouver selling panels for campers and arctic expedition vehicles. It was called Total Composites. Their tagline: "Every aspect of our panel system is engineered to solve the fundamental problems of traditional camper construction." They had me at engineered!

The Composite Advantage

• Zero Thermal Bridging

• Ultra Lightweight

• Extreme Durability

• True 4-Season Performance

• Rapid Assembly

• Material Compatibility

Our FRP pultrusions and meticulously designed panels offer near-zero conductivity, ensuring a healthier interior climate free from condensation. We have tested our enclosures in the high Arctic under extreme climate and off-road conditions, far from civilization.

In thermal camera imagery of the interior, the heated camper is roughly the same exterior temperature as the house behind it. The panels are roughly an R12 level of insulation.

Assembly & Interior Design

Next I had to find someone with the ability to take these panels and assemble them using the recommended adhesives (there are no screws or nails – only non-toxic adhesives). I also wanted to make sure they know how to use these materials, as there is a fair bit of science behind the structural properties of adhesives and composites and you want them to get it right. I found a company in Quebec called Tank Expeditions. They would assemble the unit for me and they had the training necessary to do it correctly.

Once that was settled, I had to go about designing the interior and picking the components that would allow me to meet my weight budget, thermal, fresh water, and power budgets. I started spreadsheeting (yes, I used the verb)! My training as a systems engineer was coming in handy. My training as an energy auditor was also coming in handy as I made a heat transfer calculation and power consumption calculation.

For most of the year (down to 0–5 °C), I could heat the camper just by the heat generated by me and my dog. I decided to install a small Heat Recovery Ventilation (HRV) system. This system allows us to close up the camper to keep the heat in without suffocating, as the camper is pretty airtight. Some of you have this kind of mechanical ventilation in your house. It provides fresh air and removes stale air while retaining 90% of the heat. There are very few that are built for such small volumes as a camper, but I found a system from Germany called Lunos. Everyone I spoke to had never put an HRV in a camper before, but when trying to ensure adequate fresh air without opening windows, it seemed like the logical solution. It also can dehumidify and filter the air to ensure good air quality, which can be helpful in areas with poor air quality or if you have allergies.

I would still need a heat source for those winter months, and I needed something simple that worked in very cold conditions at multiple altitudes and with a fuel source that was easy to find. I opted to get the systems they use on long-haul trucks or tractors that take diesel fuel (which you can find anywhere). This was my one concession to fossil fuels. Thankfully, my camper is airtight, well-insulated, and uses an HRV, so my calculations tell me 10 liters of diesel should last me about 1 week at -20 °C. So if I get stuck somewhere in a snowstorm, I should be able to stay warm for many days.

Weight, Water, and Materials

The mass budget was the most challenging. The camper envelope with the roof racks weighed 895 lbs, which left me roughly 1,000 lbs for everything else, assuming a budget of 700 lbs for my gear, my dog, me, food, and water.

The big concern was the weight of the water I would need as well as the weight of the interior cabinetry. For the water, the biggest issue was not to carry water for the toilet. Here I looked at 100s of toilets on the market—who knew this was such a complicated topic? I focused on composting toilets as they do not need additional water. Composting toilets separate liquids and solids to avoid bad smells. The liquid is kept in a separate airtight tank and the solids are desiccated (dried out using a fan). This helps eliminate odor and eliminates your need for water for flushing. After much research, I settled on a Swedish unit designed as part of the UN Sustainability projects for sanitation in developing countries: the Separett.

For water, I use removable water tanks from Dometic. I have 3 tanks of 11 L capacity for 33 L total (33 kg), and a grey water tank of 10 L. This can be emptied before travel. I put in a shower as well, but a shower will take at least 20 L of water if I am careful. Therefore, showers are only a last resort in the camper. Mostly I can wash with a cloth and shower in campgrounds or at a gym.

For the cabinetry, I looked at many types of material, from aluminum to honeycombed composites, birch, and wood fiber composites. I settled on a combination of lightweight wood composites which did not add too much weight and looked nice. We were careful to use as little as was structurally necessary to support the weight. These also need to be glued to the wall of the camper to keep the integrity of the camper envelope, we did not want to puncture the walls.

The windows and doors also had to be thermally efficient, so I chose double-pane acrylic windows with awning openings that allowed lots of fresh air in the summer without allowing rain into the camper. They incorporate built-in screens and insulating shades. The door is two-paneled with a screen door using two screen meshes: one for bugs (no-see-ums) and a #6 woven mesh for bears. The mesh is strong enough that a bear cannot put its claws through it. It also has a triple deadbolt system for security.

The bed in a truck camper is usually over the cab. In campers, like on boats, you want to have adequate ventilation under your mattress to ensure the dampness from bodies does not cause mold in the mattress. Here I found a product from Germany called the Froli sleep system. It was easy to assemble and comfortable to sleep on. It allows adequate ventilation under the mattress and ensures the mattress is not in contact with the cold outer surface of the camper.

Electrical, Appliances & Noise Budget

Next was the power budget. The biggest self-heating battery I could get was 300 Ah. That, coupled with 400 W solar panels, should allow me to keep a parked camper running for 4–5 days depending on shading and weather. This is the longest I usually stay in one place. When I am driving, the truck alternator will charge the batteries with 50 amps, allowing me to charge from 30% to full in about 4 hours of driving.

Next was the calculation of power consumption inside the camper. I really wanted to have a fridge and freezer in the camper as it allows me to eat healthier meals and cook more interesting meals while I travel. I found a very efficient fridge-freezer that consumes about 25 W at 20 °C ambient temp. It is a chest-style system which is very well insulated by the Dometic CFX 75.

I also have some kitchen appliances like an induction cooktop, kettle, toaster, and air fryer. I calculated how much they were consuming and how long I use them daily along with the ventilation fan in the summer, HRV in the winter, as well as the toilet and heating system. You also need to keep track of peak AC consumption as the inverter limits how much AC you can use at once. The biggest consumer of power was the induction cooktop and air fryer, and both of those don't exceed 1,500 W. I have an inverter that can provide 3,000 W if necessary.

Lastly, one big area of concern for me was the noise budget. If I travel to these lovely places for peace and quiet, I want to be able to hear it! I was very careful about selecting products which did not produce too much noise. Things like the fridge compressor, heating system, HRV, toilet fan, or the exhaust fan were carefully selected to allow a peaceful sleep. My last van had a heating system that would wake me up every time it came on, leading me to leave the heat off at night which led to some cold nights. I am pleased to say the systems make a soft background noise at night.

Summary

All in all, I am pretty pleased with how it turned out. We will see the real test this winter on some of my trips. I have access to many of the systems via Bluetooth so I can control them from apps on my phone. My idea is to keep the temp above freezing while driving and then heat up about 20 minutes before I arrive at my destination. I can also control everything from my bed, so I don't need to get out of bed in the morning to warm up the camper.

When the time comes when we have a well-developed EV charging infrastructure in Canada, I can easily port this camper to an EV truck and be a completely fossil-fuel-free traveler. I can't wait!

Michele Le Saux Board Director