There are plenty of things to consider when it comes to owning and maintaining an RV. One of the biggest concerns is understanding how to keep moisture out of your RV during winter (the time of year when most people leave their rigs unattended in storage).
Once moisture gets inside an RV, it can lead to mold and mildew, creating a health hazard and diminishing your RV’s overall value. While moisture is a potential problem year-round, it’s especially bad during winter because most people neglect to check in on their RV while it’s in storage.
Understanding Why Condensation Occurs in Winter
Most people associate moisture and humidity with the summer months. However, moisture can also accumulate during the winter months when the cold air outside an RV collides with the warm indoor air.
When cold and warm air combine, condensation forms on the surfaces inside your rig. Because your RV is closed up and there’s nowhere for the condensation to go, it eventually evaporates into the air and settles on your walls and ceiling. Before long, it creates mold and mildew, which creates a whole new set of problems.
Tip #1: Use a Dehumidifier to Control Moisture Levels
Cost: Moderate to High
Effort: Low
For most people, the battle against moisture inside an RV starts and ends with an RV dehumidifier. Dehumidifiers absorb moisture from the air and convert it into water, which sits at the bottom of a reservoir inside the dehumidifier. You will then either have to dump the reservoir yourself or run a hose from it to the outside of your rig so that the water drains automatically.
The main thing to consider when choosing an RV dehumidifier is how much area it can cover. Look for something that can cover at least 500 square feet, such as the following options:
Tip #2: Optimize Ventilation for Better Air Circulation
Cost: Low to Moderate
Effort: Low
If you don’t want to splurge on a dehumidifier or don’t think it’s the best option, you can keep the air circulating inside your RV by using vent fans, open windows, and your ceiling vent.
While leaving your windows and vents open might sound like a recipe for more RV condensation, the opposite is actually true. As long as the camper windows and vents are open and the fans are running, moisture will flow in and out of your RV.
Additionally, because the temperature inside your RV will be the same as the outside, you won’t have to worry about a hot air/cold air reaction occurring (a recreation that’s necessary to create moist air). The downside of keeping windows and vents open is that it opens your RV up to pests and critters, not to mention thieves.
Tip #3: Insulate Your RV to Prevent Cold Surfaces
Cost: Low
Effort: Moderate
With enough insulation, cold air won’t be able to enter your rig and combine with the warm air inside.
By using insulation materials like Reflectix panels on your windows, you’ll keep the inside of your RV warm while also keeping cold air out. Reflectix is a type of bubble insulation that’s especially effective at temperature regulation. Best of all, it’s very affordable and available at most hardware and RV stores.
In addition to your windows, it’s also important to insulate your doors, walls, and floors. The best way to do that is by covering them with blankets, foam mats, and rugs, as these are cheaper and cleaner options than buying a bunch of fiberglass insulation.
Tip #4: Maintain Proper Heating Without Adding Moisture
Cost: Moderate to High
Effort: Low
If you don’t want to winterize your RV before winter storage, you’ll need to keep the internal temperature fairly warm to avoid frozen water lines. While insulation will help, you’ll likely need to keep a heater running to keep the inside of your rig warm enough.
If you’re going to keep a heater running inside your RV while it’s in storage, it’s best to use electric heaters because they create less moisture. Gas heaters, like your propane RV furnace, generate a ton of moisture, which can lead to mold.
Whether you choose a gas or electric heater, it’s always a good idea to keep a dehumidifier running whenever the heater is in use. After all, using a dehumidifier is the only surefire way to know that your RV isn’t filling with moisture.
Tip #5: Manage Moisture Under RV Mattresses
Cost: Low to High
Effort: Low to High
One of the most forgotten hotspots for moisture buildup inside your RV is under your RV mattress. Mattresses are a great place for moisture to build up in secret where no one can see it. Then, before you know it, you have a mold infestation on your hands!
Several things can be done to prevent moisture buildup underneath your RV mattresses. First, you can wrap it in a mattress underlay to keep moisture out. However, fair warning: an underlay isn’t always effective at completely preventing winter condensation.
Therefore, you can either invest in a ventilated mattress or install slats or a wooden mattress platform to give your mattress breathing room.
Tip #6: Reduce Moisture in the Kitchen and Bathroom
Cost: Low
Effort: Moderate to High
Aside from underneath your mattress, our kitchen and bathroom are breeding grounds for moisture build-up that can lead to mold. In addition to the baseline condensation risk that every room in your RV is susceptible to, kitchens and bathrooms are at increased risk because water is used in these areas regularly.
Proper winterizing your RV is the best way to keep moisture out of your kitchen and bathroom. During winterization, you remove all water from your water lines and blow them completely dry.
If you don’t want to winterize your RV, you should definitely invest in a dehumidifier and exhaust fans. Otherwise, the moisture from your water lines will eventually creep into your RV, evaporate into the air, and create mold.
Tip #7: Use Moisture Absorbers in Small Enclosed Spaces
Cost: Low
Effort: Low
Along with your RV mattress, small enclosed spaces are other often forgotten hotbeds for moisture accumulation. These nooks and crannies, such as cabinets and storage compartments, are especially prone to moisture because there’s no airflow, and dehumidifiers can’t always reach them.
Luckily, you can use moisture packets and absorbers, such as Damp Rid, to reduce condensation in these areas. To do this, simply hang the moisture absorber in the area in question, and humid air will naturally flow towards it. Moisture absorbers typically cost anywhere from $5 to $15 and are well worth the investment.
Tip #8: Seal the Roof
Cost: Low
Effort: Moderate to High
Thus far, we’ve discussed how to keep moisture from getting in through your doors, RV windows, and floor. However, one of the easiest ways for moisture to enter your RV is through leaks in your roof.
As such, it’s important to check your roof for leaks, cracks, and holes before putting it into storage. In your inspection, be sure to check around the flashing, seals, and corners of your roof.
If you notice any issues, use caulking to seal the problem areas.
Tip #9: Keep Your Cabinets Open
Cost: Low
Effort: Low
If you don’t like the idea of moisture absorbers or think they won’t be effective enough, you can also keep your cabinet doors open. That way, moisture can’t get trapped inside of them and create mold and mildew.
Tip #10: Check Humidity Levels Regularly
Cost: Low
Effort: Low
When most people store their RVs for the winter, they plan to leave them in storage until RV season rolls around (and very few think to schedule routine check-ins). However, even if you have the best plan to prevent moisture, no plan is foolproof. Therefore, it’s important to check the humidity levels inside your RV regularly.
The best way to monitor humidity levels is to place several digital hygrometers inside your RV. Hygrometers are essentially like thermometers, but for humidity, and will tell you the humidity percentage. As long as it’s below 50%, moisture likely won’t build up, and your RV will be safe.
While you’re checking the humidity levels, you should also check to make sure any devices you’re using are working properly. That includes your dehumidifier, heaters, and vent fans.
Final Thoughts
In addition to everything we just covered, where you store your RV plays a huge role in keeping moisture out of it during the winter. For instance, storing your rig in a climate-controlled building or facility is the best way to keep your RV warm and dry during the winter months.
If you don’t have a climate-controlled storage option on your property, consider using Neighbor, a peer-to-peer storage marketplace. With Neighbor, you can find climate-controlled storage options near you so that your rig is safe, dry, and ready to go if you want to take it out for some winter camping!
Frequently Asked Questions
Can I Use a Propane Heater in My RV During Winter Without Causing Condensation?
Propane and other gas-powered heaters are notorious for generating condensation when they produce heat, so they shouldn’t be used in a stored RV.
How Often Should I Check the Humidity Levels in My RV?
You should check the humidity levels in your RV every week or every other week at minimum.
Can Moisture Absorbers Prevent Mold in All Areas of My RV?
Moisture absorbers have a small and limited range and can only prevent mold in small, enclosed areas of your RV. The best places for them are under your bed, in storage areas, and in your cabinets.
