Can We Create Housing from Used Cars?

Converting used cars into tiny houses—often referred to as “car-camper” conversions or “micro-dwellings”—is a creative way to upcycle machinery into a functional living space. It’s estimated over 10 millions vehicles are scrapped every year in the US. Repurposing just a fraction of that could create sufficient low-cost and emergency housing stock to make housing less expensive. Because cars are designed for movement rather than habitation, the process requires specific modifications to manage insulation, space, and utility.

• Heating/Cooling
• Ventilation
• Privacy
• Plumbing

Managing the temperature in a vehicle-based tiny home is significantly harder than in a traditional house because of the low thermal mass of metal and the high surface area of glass. To stay comfortable, you need a combination of “passive” strategies (retention) and “active” systems (generation).

Insulation: The First Line of Defense

Before adding heaters or AC, you must slow down the heat transfer.

• Reflective Window Covers: Most heat enters and escapes through glass. Custom-cut Reflectix or Blackout panels are essential. Reflective side out in summer to bounce sun away; black side out in winter to absorb radiant heat.
• Thermal Curtains: Hanging a heavy, insulated curtain behind the front seats (the “cab area”) creates a smaller zone to heat or cool, as the large windshield is a major source of temperature loss.
• Gap Filling: Use spray foam or wool in the “ribs” and pillars of the car body to eliminate cold bridges.

---

Heating Sources

Heating is generally easier to manage than cooling because it requires less power.

• Diesel/Gasoline Heaters: These are the gold standard for van and car dwellers. They tap into your fuel tank (or a separate small tank) and vent exhaust outside. They provide dry, intense heat without the moisture buildup common with propane.
• Propane Heaters (e.g., Mr. Heater Buddy): These are portable but risky. They release significant moisture (causing condensation/mold) and consume oxygen. If used, a Carbon Monoxide detector and a cracked window are non-negotiable.
• Electric Heating Blankets would be an ideal solution if an outside electric power source is available.

---

Cooling Solutions

Cooling can be even more difficult than heating. In the winter, body heat alone can be the solution with a good sleeping bag, but, in the summer, that ally becomes an enemy. The human body can give off 100 watts of heat at rest and much more in motion. This energy along with the heat from outside the car most be managed.

• 12V Roof Fans: These don’t lower the temperature, but they provide “active ventilation.” A fan like a MaxxAir creates a wind-chill effect and pulls hot air out of the ceiling while drawing cooler air in from the floor.
• Portable Dual-Hose AC: Units like the EcoFlow Wave or Zero Breeze are designed for small spaces. They are 12V/24V compatible, though they still require a large battery bank or “shore power” (plugging into a wall).
• Evaporative (Swamp) Coolers: These only work in very dry, arid climates (like the Southwest). They use water evaporation to cool the air, but in humid environments, they only make the air feel “stuffy.”

---

Energy Management

To run active heating or cooling, you’ll need a robust power setup:

• Solar Panels: Flexible panels can be mounted to the roof to trickle-charge your system during the day.
• DC-to-DC Charging: This allows your car’s alternator to charge your “house” battery while you are driving.
• Portable Power Stations: Units from brands like Jackery, Bluetti, or EcoFlow provide an all-in-one battery, inverter, and charge controller to plug your devices into.
• External Power: Ideally, external power would be available.

Not only must the interior temperature be managed, but the humidity level requires attention as well. Here human physiology adds challenges. People can give off 400 ml of liquid water as vapor a day. In the winter this can result in ice on surfaces, and in the summer it can make heat seem even more uncomfortable.

1. The Golden Rule: Ventilation

The most important step is providing an exit path for the moisture.

• Crack the Windows: Even a half-inch gap in two diagonal windows creates the cross-ventilation necessary to move humid air out.
• Rain Guards/Window Deflectors: These are highly recommended. They allow you to keep windows cracked for airflow without worrying about rain or prying eyes seeing that the window is open.
• Sunroof: If your car has one, tilting it open is an excellent way to let rising warm, moist air escape.
  

2. Air Circulation

Stagnant air is where condensation thrives.

• USB Fans: Small, rechargeable fans positioned to blow air toward an open window or across the ceiling can prevent moisture from settling on surfaces.
• Avoid Recirculation: If you run the car’s climate control briefly before bed, ensure the “recirculate” button is off so you aren’t starting the night with trapped humidity.
  

3. Absorption and Barrier Methods

If ventilation isn’t enough, you can try to catch the moisture before it hits the glass.

• Desiccants: Products like DampRid or reusable silica gel canisters can help, though they often struggle to keep up with the high volume of vapor a human produces in a small space. They work best in smaller, sealed bins rather than the whole cabin.
• Window Covers: Using custom-fit Reflectix or insulated covers creates a thermal barrier. By keeping the glass surface “warmer,” the vapor is less likely to flash-freeze or liquefy against it.
• Microfiber Towels: Always keep a dedicated microfiber towel handy to wipe down the inside of the windshield first thing in the morning. This prevents the water from dripping into the dashboard electronics.

4. Moisture Source Control

• Don’t Dry Gear Inside: Avoid hanging wet socks or towels inside the car overnight.
• Cook Outside: If you are using a camping stove, never do it inside the vehicle. Combustion releases significant amounts of water vapor (and carbon monoxide).
• Breath Direction: If it’s extremely cold, try to sleep so your face isn’t directly muffled by blankets, which traps moisture in your bedding, but also isn’t aimed directly at a side window.

Creating in a car the features that plumbing allows in a typical house is particularly challenging.

• Toileting Solutions
  • The “Luggable Loo”: A simple 5-gallon bucket with a snap-on toilet seat lid. You line it with a heavy-duty compostable bag and use an absorbent powder or cat litter to manage liquids and odors.
  • Folding Toilets: These are metal or plastic frames that hold a bag. They take up very little space in the trunk compared to a bucket.
  • Cassette/Chemical Toilets: These have a built-in freshwater tank for flushing and a waste holding tank. They feel the most like a “real” toilet but require more maintenance and a proper dump station to empty.

Keep a dedicated “bathroom bag” (a small dry bag or packing cube) so you aren’t hunting for supplies in the dark. It should include:

• Toilet paper and/or wet wipes.
• Hand sanitizer (essential).
• A small trowel for digging.
• Opaque sealable plastic bags (for disposing of used wipes or paper).
• A headlamp.

• Showering Solutions