Winterizing RV Tips You May Not Know

Properly preparing your RV for winter storage takes some effort but it's essential not to overlook these important DIY steps.

Winterizing your RV is just one of the mandatory annual tasks that comes with ownership. Even though you may follow a thorough step-by-step checklist, it’s often the missed minor details that can cause the most damage in some of the most unsuspecting areas of your trailer or motorhome. 

From invading pests to unexpected leaks, moisture and mildew, the following points are just some of the added precautions to take when winterizing your RV. While some tasks may already be included on your checklist, it never hurts to double check or reinforce your efforts to ensure continued reliability of your rig for next season. 

Plumbing, Wires and Mice (or Other Pests)

Just like your home and the adjoining garage, basement, shed, and attic, RVs are very vulnerable to mice and once they get in, these furry little pests will like your RV even more than you do. 

Harmless to humans yet annoying, mice can go to town on wires, rubber lines, upholstery, or almost anything they can sink their little teeth into, thus causing serious and costly damage. If you own a travel trailer or fifth wheel, be sure to inspect the underside of the unit, storage areas and other compartments for any cracks, holes or any existing cutouts that run lines, piping or electrical wires. The smaller the opening that you find to fill, the better. No hole or gap is too small for a curious mouse. In fact, with their fairly flexible rib cage they can squeeze through the tightest of spaces, as tiny as 6 to 7 mm.  

Yet, regardless of what style of unit you own, try to locate any possible entry points behind drawers, in larger basement storage units, as well as behind cupboards, appliances, furniture, and around slideouts. It’s best to do this on sunny days when it’s easier to locate light streaming through holes, cracks or gaps that shouldn’t exist.

But, it’s not impossible to stop these relentless pests from setting up a nice home in your RV. A sure-fire way to plug these gaps is by using spray foam, which is widely available at Home Depot, Wal-Mart or RV service centres at little cost. It’s easy to use and a little goes a long way. Caulking for smaller gaps is also effective as is plugging areas with steel wool, just as you would do at home. 

Further prevention is the use of mice repellents (or other repellents for pests like squirrels or chipmunks) and there’s a wide variety of solutions available. Another preventative effort is storing your RV on a hard surface rather than in areas with tall grass or other environments where mice and pests may inhabit in the fall before the snow flies. 

It’s also wise to check your RV throughout the winter as you can use these preventative measures immediately if you see any signs of mice or other intrusive creatures to reduce the risk of any damage. Above all, every RV stored for the winter should be free of food, drinks, crumbs, even spills. Neatness always counts. Don’t provide a reason for mice or pests to enter in the first place.

Check for ANY Leaks 

Water can be the number one culprit to damage  in any RV and while you have the calking gun out, remember those small cracks can also cause water to leak in throughout the winter, potentially causing major damage. Water leaks can occur in a variety of areas so be sure to double check all seals around windows, doors, slide-outs, seams of the top corners where the walls and ceiling meet, cutouts for systems on the roof and roof seams at the front and rear of the unit. Also be sure to use an appropriate sealant for the material you are sealing or reach out to your local RV dealer to address any concerns. 

At the same time, look for any discoloration or soft spots in these areas as they are sure signs of water intrusion. Fix them immediately. Also inspect all designated storage compartments as well as the interior and exterior areas where the water heater, furnace, exterior shower, potable water fill and city water inlet are located. 

Add Stabilizer to the Fuel Tank

Any automotive engine - including the one in your winterized motorhome -  that sits for prolonged periods needs to be treated with a fuel stabilizer since gas will start to oxidize and deteriorate after about a month or in storage (diesel fuel takes a little longer). Fuel stabilizers like STABiL or Biobor JF (available for both gas or diesel engines) provide a protective layer for the fuel to prevent evaporation during extended periods and stubborn resin deposits from forming, which can damage the carburetor or other fuel components over time. 

To use, start with an empty tank of fuel (or nearly empty), add in the appropriate amount of stabilizer as per the manufacturer guidelines, and then top up the tank with fresh fuel. This will disperse the stabilizer with gasoline and ensure the tank is minimally exposed to air or water. Next, simply start the engine and let it run for approximately five to ten minutes to allow the stabilizer to reach the entire fuel system. 

Mould and Mildew Build Up in Unforeseen Spaces

If you’ve ever forgotten to roll up the RV awning after driving away from a campsite, there may be a chance you’ll forget about the importance of cleaning and ensuring it’s dry before winter storage. 

Being out of sight when it’s not extracted, an awning is easy to overlook and should always be completely dry before winter storage to prevent mould, stains, and a stubborn odor that will develop over the winter.  If it’s on your checklist, double check it just to be sure. But if it’s still moist from the rainfall from that one last trip, simply roll it out for an afternoon to dry and then roll it back in just before storage. The same should apply to pop-up campers or other commonly exposed fabrics. 

Other ways of preventing mould and mildew include using a high quality breathable RV cover (if your RV is stored outdoors) that can vent water vapour from forming, running a dehumidifier a few times during storage, and of course, checking for leaks to prevent water intrusion. 

Preparing your RV for winter storage is not difficult but it does take some time, effort, and knowledge of your systems to ensure they will work and function as they should next season.