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How to Reduce Moisture and Prevent Dampness in Your RV

Julie is an RV enthusiast with lots of helpful information for readers.

Follow these simple steps to manage the moisture levels in your RV motorhome and prevent dampness

Follow these simple steps to manage the moisture levels in your RV motorhome and prevent dampness

Why Is It Important to Manage the Moisture in an RV Motorhome?

It is vitally important to manage the moisture levels in any RV, motorhome, or caravan because if you don't, the space can become damp. And if the space becomes damp, it is very hard to sort out and get rid of that damp. Dampness will affect every part of the living space. It will get into the wood, walls, cushions, mattress, and curtains. It will become damp and cold to the touch, and mold and mildew will start to appear.

Damp and moisture levels in RV motorhomes are a big problem to the point where it is strongly advisable to get a habitation check done BEFORE you buy one to make sure the moisture levels are not too high. It can cost thousands to correct if there is a problem, and there are horror stories about this all over the internet.

Luckily, preventing damp and excess moisture is easy just by taking a few small steps and following a few simple procedures.

Six Simple Steps to Manage the Moisture Levels in Your RV

  1. Keep your RV motorhome well ventilated.
  2. Whenever you boil the kettle, cook, or wash up, steam is produced. Open the window next to the cooking area to let the steam out. Also, keep the lids on pans when you cook.
  3. Whenever you have a shower or wash, open the roof vent in the bathroom/wetroom, and if possible the bathroom window too, to let the steam out.
  4. Don't underestimate how much Co2 and therefore condensation we produce by breathing—especially when we sleep. So try to leave a window or roof vent open during the night. Most RVs are kitted out with fly nets to prevent bugs from getting in.
  5. Always wipe up excess moisture straight away. Although the showers and sinks will be sealed, any moisture left hanging around can gradually seep into the woodwork and cause dampness. Wipe it up.
  6. Don't create excess water and steam. For example, don't leave a kettle boiling for minutes (we use a steam kettle in the van to save electricity), instead, pour it as soon as it boils.

These six steps are very simple, easy, and effective ways to reduce the moisture levels day to day. However, these steps alone probably won't be enough for most RV users, particularly if you use it regularly, are a full-timer or you are concerned about the moisture levels. Read on to find out what else you can do.

Options for Managing Damp and Moisture in Your RV Motorhome

I believe that some American RVs have built-in extractor systems; however, our motorhomes here in the UK don't, so I will deal with this as though you don't have an extractor system.

Having researched this we found that there are two main choices: moisture-removing crystals or an electric dehumidifier. There are pros and cons to both. Let's take a look.

Moisture-Removing Crystals

Moisture-removing crystals simply suck in the excess moisture from the air and trap it.

Pros of Moisture-Removing Crystals:

  • Easy to use
  • Clean
  • Cheap

Cons of Moisture-Removing Crystals:

  • Chemicals. Although this won't bother some people, it is a big con for us. I don't like to have extra chemicals in my home, and so I will always choose an electric dehumidifier over the crystals.
  • There is a risk that pets could eat or lick the crystals, although you can buy them in containers with lids, such as the ones shown below, to reduce this risk.
  • Have to replace the crystals every now and again, approximately every couple of months.

As a typical RV, motorhome or caravan is quite a small space, you only need a small amount of the crystals. You can buy them loose from Amazon or a specialist RV place. Below I have shown the crystals available in a container, and also dehumidifying eggs, which utilize the same principles and are neat and nifty. A wardrobe dehumidifier is fine for an RV, as it is a small space.

Electric Dehumidifier

Another very popular way to keep the moisture levels in check in your RV is to use an electric dehumidifier. There are many available on the market. It is better to choose one that is specially designed for use in a motorhome, or choose a very small one, as standard dehumidifiers for houses will be too large for your motorhome.

'Eva Dry' makes very good small dehumidifiers. You can get a really small one (petite), which collects approximately 1 liter, or a medium-small one, which collects approximately 2 liters. Which one you choose will depend a lot on your environment and how damp it is. We went for the smaller one.

Pros of an Electric Dehumidifier:

  • Small and easy to use
  • Works really well
  • Pet safe
  • No chemicals
  • You don't have to keep buying replacement crystals

Cons of an Electric Dehumidifier:

  • You have to empty the water collection tank roughly every two days depending on the size of the RV and the steam you produce.
  • Uses electricity, which is not much good if you are relying on your battery and have no electric hookup.
  • Can sometimes leak a little and leave a small puddle, although it does shut itself off when full. Personally, we have never had this problem with this dehumidifier; however, I read it in some of the reviews.

Eva Dry Electric Dehumidifier

Which Is Better: Moisture Removal Crystals or an Electric Dehumidifier?

Another Little Tip

Finally, it is a good idea to keep a tube of sealant handy so that if and when any gaps in the sealant around your sinks and shower appear, you can easily and quickly seal them back up again to prevent moisture from seeping into the bodywork. Remember to dry the area before applying sealant and leave plenty of time for it to dry afterward before getting it wet again.

This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters.