How do you stop condensation in the back of a van?

In this article, we will answer the following question: How do you stop condensation in the back of a van? We will explain why condensation is forming in the back of a van and how to prevent it. 

How do you stop condensation in the back of a van?

While completely stopping condensation in the back of a van may be a challenge, you can at least try to prevent and reduce humidity.  This goes through the important stages: good insulation, thermal bridges and efficient ventilation.

  1. Having good insulation is essential: First and foremost, having a well-insulated van will protect you from excess humidity. To do this, if you are designing your vehicle yourself, take the time to study the different materials and their characteristics. 

Rock wool is a good sound insulator but fears moisture, expanded polystyrene resists moisture but is not breathable … In fact, it is often the combination of several insulators that will give you optimal results!

  1. Check thermal bridges: A thermal bridge, in a van, is a bridge between a cold temperature and a hot temperature. It is a “hole” in the insulation that will bring in cold air in winter or heat in summer. 

To limit humidity in your vehicle, you must therefore hunt for these bridges! And it is often on the ground, along with the structure or stringers or at the level of doors and windows that they reside. To identify them, just run your hand over the walls to spot the temperature differences.

And to overcome it? We isolate! Sprayed cork is an excellent insulator just like Armaflex. More difficult when it comes to hollows, you can “stuff” the holes with wool.

  1. Provide adequate ventilation to avoid humidity in the back of a van: The last essential point to limit humidity in a campervan: ventilate, ventilate and ventilate! You need to ventilate your cabin as much as possible to circulate the air. A constant flow of air from the bottom up pushes moist air and brings in dry air. Easier to do in summer than in winter you will say … But ventilation also goes through the air vents and skylights!

Ventilation systems are essential and mandatory in a van. To know the number of grilles to install or their sizes, you must comply with standard safety ventilation requirements. Depending on the volume of the van and the number of people, you will obtain the number of grids to install. 

But there are also other ventilation systems for your van:

  • The skylight: the most popular solution, it is installed on the roof of the vehicle (thus drilling the sheet metal) and offers permanent ventilation. We also benefit from a beautiful skylight. It can be fully open or partially open, especially for winter.
  • Shutter or electric fans: for classic fans you will have a wide choice in specialized stores or online. They can be fitted with mosquito nets. You can also choose grilles with shutter (sliding part for closing from the inside) or electric grids but which therefore require a connection or solar panels.

What more can you do to limit condensation in the back of a van?

First, to limit condensation and water vapour, think of simple things: put a lid on your pots when the water is boiling! For your laundry, avoid drying it indoors as much as possible: in summer, no problem, but it is true that in winter it is more complicated (discover the different ways to wash your laundry on a road trip).

You can equip yourself with a dehumidifier to remove moisture, especially in the bathroom, if you have one. The classic version works with blocks of salt (placed in a box) which will take care of the ambient humidity. The last several weeks and taken up little space. 

Count less than 10 $for the purchase but also think about top-ups. There is also an electric version, which is certainly more efficient, but which will require you to be connected to electricity. They operate on 12 V or 220 V and cost between $50 and $100.

What is condensation in a van and how to prevent it?

Simply put, condensation is water that collects in droplets on a cold surface when mixed with moist (humid) air. In other words, at night when you sleep in your hot van, water droplets collect on the windows and any other surface cooler than the air inside your van.

Have you ever encountered the dangers of having mold in your home? Let’s say it’s not pleasant! A constant cough, sore throat, eye irritation, and decreased immune function are just a few of the reasons why it is VERY important to do everything in your power to prevent a mould outbreak in your van.

Another thing that condensation can cause is rusting. As? Well, mix some water with an exposed piece of metal and you have a chance that some rust will form (eventually). Mix it with winter road salt and you’ll have all of the van lifers’ nightmares.

Although it can be almost impossible to prevent the fact that rust eventually forms on most (if not all) vehicles. It’s up to you to do your best to shorten this period and increase the longevity of your home.

Another thing that condensation can do in your building is cause it to rot. If there is enough condensation to collect, sensitive parts of your building will eventually rot. Think cabinetry, ceiling tiles, or anything wood-related. The rot itself will eventually cause rust and mildew. Something I don’t think anyone would dream of.

How condensation forms in the back of a van

Condensation forms with moisture in the air. It then attaches to a surface cooler than the air itself. That’s why you see it mostly in windows, but sometimes on the interior roof and everywhere else that hasn’t been properly insulated.

Where does this moisture come from? Most often, your breath! When you spend time in your van, the air your breath releases will likely be warmer than the air inside your home. Are there two people and a dog living in a van? This is increasing exponentially!

Alternatively, it also comes from cooking without proper ventilation. If you boil water, steam vegetables, or fry something delicious, all that moisture will be put into the air as well.

Another place where condensation comes from is your heating source. Some are better than others. For example, propane noticeably creates more moisture than other alternatives. A diesel heater is commonly referred to as dry heat and releases half the humidity of a propane heater.

How to clean the condensation from the back of a van?

So you wake up in the morning and the windows are covered in the irritating condensation that you worked so hard to avoid. What should you do?

No matter how tempted you are to turn around and go back to sleep, don’t! Instead, take a very absorbent cloth or paper towel and wipe off the water as best you can. It can be easy to miss a day and suddenly a month has passed and your van smells a little bit bad.

Another option for cleaning is a wet vacuum –  it helps reduce wasted paper towels and makes the process a lot easier.

The bottom line

Besides all the above-mentioned options, there are many other tricks and tips that campers use in order to keep their vans condensation free. If the humidity level regularly exceeds 70%, it can cause rust, mould, musty odour and rot. To remedy this, dehumidification must be carried regularly and using a good dehumidifier might be the best investment for your van and your health!

If you have any comments or questions about the content, please let us know!

FAQ in How do you stop condensation in the back of a van?

Humidity in a van: how to avoid it?

To avoid humidity in a van:

  • Insulate your van (and insulate it well)
  • Install double-glazed windows or add an over-glazing film on its basic windows.
  • Use lids in the kitchen.
  • Buy a moisture absorber
  • Open your cupboards and cabinets from time to time.

How to avoid condensation in a motorhome?

Running a fan can help evaporate condensation and evenly distribute the air temperature throughout your motorhome or caravan. If you have a window or an open vent, a fan will help the moist air to escape faster.

How to ventilate a van?

To ventilate the van, there are several possibilities:

  • Place racks on the sides of the van. In this case, proceed as for low ventilation.
  • Install ventilation mushrooms on the roof. Inexpensive but the discharge volume is quite limited.
  • Install skylights on the roof

How to ventilate a motorhome?

To ventilate the interior of your motorhome, get a fan. To provide fresh air, the trick is to place a damp towel on it or put a bowl of ice cube in front of it. The turbo-vent is a device which can be fixed to the ground but which will gain in efficiency if it is placed at the level of the skylight.


Was this helpful?

Thanks for your feedback!