5 Tips on Preventing Thermal Transfer

I think we’ve all had that experience while sleeping in our campers, of being woken up by a moisture drop falling on our face. It’s cold and not a great feeling, right? You may have wondered, why are there raindrops INSIDE the van? Well, the scientific answer is that there is thermal transfer happening. Cold air is being transferred through cold surfaces into a heated space which causes the moisture drops. 

Another word for thermal transfer is condensation.

Condensation- What is it?

To be short, condensation forms when warm air hits cool surfaces. It's the process where water vapor becomes liquid. (The opposite of evaporation, where liquid water becomes vapor).

Just like on a hot day, condensation is formed on an ice cold glass. 

The tighter the space, the more thermal transferring is likely. That is why it is a common problem and talked-about topic amongst the van life community. The space is tight, there is a lot of metal therefore it is very easy for the cold air from outside to come into contact with the warm air inside. Having metal window frames, walls, ribs and rivets are perfect culprits for the cold air to transfer through into the inside of the van. 

It’s why insulation is necessary as it slows the rate of the heat being transferred in and out of your van or camper.

It’s why having a high insulation value (like +R20) is recommended because it’s able to resist heat transfer.

5 tips to Prevent Thermal Transfer

1. Proper ventilation!! This is key. You want to bring cooler, drier air inside while pushing the humid air out. A fan or cracking a window is important when you are doing activities where you are adding moisture to the air such as cooking or are running a propane heater. 
   
   
2. Use a diesel heater. Diesel heaters ventilate externally, they do not add to the overall moisture of the air and they lower the relative humidity. They also have a temperature preset and a low fuel consumption. We have another blog post on Diesel Heaters because we love them that much- you can find it here.
   
   
3. Choose your windows wisely. Windows are the direct buffer between the cold outside air and the warmth inside your van. Having a metal window frame or windows without insulation doesn’t give you a fighting chance to prevent condensation. Check out Arctic Tern Windows here. They are double pane acrylic windows and are the best that we’ve seen so far on the market.
   
   
4. Don’t hang up wet clothes to dry inside your camper. This adds moisture to the air which in turn can cause mold on your clothing. Gross! Always, always, always hang them up outside. We use a window drying rack that latches onto the camper window allowing  for air flow circulation while also drying the clothes at the same time. Score one of those here.
   
   
5. Insulate exposed metal. When condensation forms on metal, it has nowhere to go and can quickly turn into rust. It also reduces the effectiveness of insulation.

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