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Whether you’re going to be camping in the snowy season in your RV or need to put your rig into storage before winter comes, there’s a long list of things that need to be done to make sure you can survive the harsh winter or to safely keep your valuable motorhome in tip top shape during storage. Learning how to winterize an RV, both for camping preparation and storage, will ensure enjoyable camping experience and proper maintenance for your RV.

This comprehensive guide on how to winterize an RV will teach you all the necessary preparations from seasoned RVers to keep you and your precious vehicle safe and well. 

The first part concerns how to winterize an RV for camping in extreme cold weather: affordable and sustainable methods for keeping your rig warm without eating up electricity. The second part focuses on how to winterize an RV for storage: everything you need to do so that when the next camping season comes, so that you won’t need to deal with expensive repairs and maintenance before hitting the road, such as keeping pipes from freezing and busting.

how to winterize a camper
It’s necessary to winterize your RV for camping and for storage before winter comes.

How To Winterize An RV For Camping: Keeping It Warm & Toasty

Heating using gas, electricity or propane can be big money pits in winter. Since your RV batteries drain very quickly in winter, plugging in at an RV park is the best option for winter RV living. However, if you love to travel off the beaten path and won’t have easy access to a campground power outlet, knowing how to heat an RV without electricity and propane will be a matter of survival during icy months. 

The following methods are passive heating techniques that effectively trap the heat inside your RV and prevent icy cold air from leaking in. Even if you use conventional heating, these techniques can add considerable warmth to your journey while being affordable and saving you heaps of money in the long term. 

The key to keeping your RV warm in the harsh winter is effective insulation, that is preventing cold air outside from leaking in and trapping the heat inside the RV. The two areas to focus on are windows and vents. 

1. Windows: Reflective insulation and air leaks sealing

Maximizing natural sunlight

You might think that trying to get exposure to sunlight when it’s snow and ice outside would not do much, but you would be wrong. Simply positioning your RV so that the largest windows point to the south and west to maximize your RV’s exposure to direct sunlight definitely will warm your RV up. 

Fixing air leaks

Before trying to do anything to more effectively trap warm air inside your RV, you must make sure cold air cannot leak in from all the nooks and crannies first. 

Tiny air leaks from the rubber gaskets around your exterior windows, doors and vents are often overlooked, however keeping them in good shape will ensure cold air is not leaking into your interior. 

Reflective insulation

If you love to travel in the winter, Reflectix is something you must equip your RV with. Relectix is a reflective insulation accessory consisting of an aluminum foil, which covers all your windows to rebound most of the heat that travels to them. Thus the existing heat will be trapped or condensed inside your RV while only a small amount will escape, thereby more effectively maintaining the ideal temperature. 

These rolls typically cost around $15-$30 each, an economical and effective way for cheap and effective temperature control. Simply attach these rolls to cover the whole area of each window. Also, if your RV comes with a shower skylight, don’t forget to insulate it too.

A pro tip on how to heat an RV using Reflectix is to look at the product’s R-value. This R-value tells you how well the insulation will trap heat inside a space.

While the higher the R-value number, the better, anything between R-3.7 and R-21 would be functional for your RV’s relatively small space.

2. Hatch vent insulator

winterize RV hatch vent insulator
An RV hatch vent insulator.

An RV’s hatch vents, roof and wall vents are also often overlooked and can let cold air in, thus all of them need to be covered. These vents covers are usually made from thin plastic, which is not reliable at all in preventing cold air from leaking in. Thus it is best to equip them with extra protection by adding another layer of Styrofoam right below the covers. 

The Styrofoam must be cut to fit precisely. Secure it in place with tape or another adhesive.

The second option is to get a vent insulator, which typically sells for around $15. A vent insulator is a large piece of insulated foam that may or may not come with a reflective surface. Do note that you must get a vent insulator that will fit your vents.

Otherwise, when you’re done camping for the year, and it’s time to leave your RV dormant for the winter, you need to take appropriate steps to prepare your rig for storage. Follow these steps below on how to winterize an RV so that when the next camping season comes, you won’t need to deal with expensive and time-consuming repairs and maintenance.

How To Winterize An RV For Storage: Tools You’ll Need

Below are the tools you will need, which are all available on Amazon or your local auto stores:

  • RV Antifreeze
  • Blow-Out Adapter
  • Air Compressor
  • Water Heater Drain Socket
  • Winterizing Kit: this might already be built into your RV.

Some RVs come with this kit already installed, but even if yours doesn’t, you can easily get one and install it yourself. An RV winterizing kit typically costs around $10-$15 and the installation should only take about 15 to 20 minutes.  

RV winterizing kits essentially consist of a valve and a hose.  Simply attach the hose to the open port on the kit and then flip the valve to the winterize position.  This will pump antifreeze in all of your water lines to protect it from freezing and busting.

The winterizing kit is installed on the line that connects your freshwater tank to the water pump.  Like the water heater bypass, this is usually located behind an access panel. If you don’t know where the panel is, locate your water pump based on its sounds while running and look for a panel near that area.

How To Winterize An RV For Storage After You’re Done Camping 

Below are the most important items that need your absolute attention when winterizing a camper before putting it into storage during the whole winter months, when many things can happen to your RV when you’re not looking. For more on how to properly take care of your precious investment, refer to our comprehensive guides on DIY maintenance.

drain RV water line
Draining your RV’s plumbing is the first step to winterizing your RV.

Drain Your Water Tanks

It’s extremely important to not let waste water sit in your RV all winter long. Not only can those tanks be a breeding ground for bacteria, the water can freeze in extreme weather, causing many expensive issues. 

  • You will need to flush both the black water tank first and then the gray water tank.
  • Once both are drained, if your RV does not come equipped with a built-in system, clean the black tank with a special cleaner designed for cleaning these tanks or a cleaning wand.
  • Take all the tanks’ contents to your local dump station.
  • Allow all water to drain from the fresh water holding tank. To do so, you’ll need to open the “petcock.” 
  • At this point, do not drain the water heater yet. It should only be done after you have added antifreeze to your water lines.

Attach an air compressor to the water lines

To make sure the water lines are emptied, you’ll need to blow air into it with an air compressor. For that, you will need a compressed air adapter. It is commonly known as a blowout plug, which can be purchased at all hardware stores and probably your local supermarkets. 

  • To force any remaining water out of the water lines, use a standard air compressor, such as one used to inflate tires, to blow air through the water lines. This is not a must, however it helps to keep your antifreeze from becoming diluted, which will reduce its effectiveness.
  • Pressure should be 30 pounds per square inch or maximum of 50 psi.
  • Replace caps on all the drains, and close all the cold and hot water faucets.
  • Reclose your petcock.
  • Detach the air compressor and the adapter from the RV. 

Drain Your Water Heater and Water Lines

Now you can move on to flushing the water out of your water heater. 

  • You need to turn it off and let it cool down and not be under pressure. Don’t drain the water heater if it’s hot or as pressure built up. In this case, you must wait until the temperature and pressure come down.
  • Then, you can remove the drain plug and then open the pressure relief valve. This will drain the water in the water heater. 
  • Note: If you want to drain the water heater faster, pull the pressure relief valve to allow air to enter the top of the tank.
  • While the water is emptying from the drains below your RV, locate a large hex plug at the bottom of the water heater.  
  • Usually the heaters anode rod will be attached to the plug.  Remove the plug and inspect the anode rod. If the anode rod is more than ¾ gone then you should replace it.  
  • After all the water has been drained, close any open fixtures and drains.
winterize RV water heater
The anode rod on the left shows corrosion and should be replaced to keep your water heater in good shape.

Open any cold and hot water faucets

  • After the water tanks, flush all water faucets, including those for the sinks, toilet and shower. 
  • Flush your toilets a few times to ensure all the water’s gone.

This helps drain all of the rest of the water out of the system.

Bypass Your Water Heater

Before adding antifreeze to your RV’s water line to keep it from freezing, you need to make sure you bypass the water heater to make sure antifreeze won’t be making its way into the water heater. Some RVs will have one, maybe even two or three, bypass valves already installed. 

To bypass your water heater:

  • Turn off the water heater;
  • If you’re installing the bypass valve for the first time, disconnect the hot and cold lines going in and out of the water heater;
  • Connect the bypass valve, following the instructions on the package;
  • Close off the same hot and cold lines and open the bypass valve.
  • For normal operation, close the bypass valve and open the hot and cold valves.

Adding Antifreeze to the Plumbing System

There are three methods of adding antifreeze:

  • From the inside, using a water pump conversion kit;
  • From the outside, with a hand pump;
  • With or without a bypass. 

The science behind the three methods is the same. However, without a bypass, you will have to add much more antifreeze if you choose either the first two methods. Therefore, we’ll be addressing the bypass method. 

winterize an RV antifreeze
Adding antifreeze to you plumbing will prevent your water line from freezing.
  • Disconnect the water line that connects the fresh water tank to the fresh water pump. Attach the pump upstream of the water tank. That is, the antifreeze will go in before the tank.
  • Prepare the antifreeze jug: Approximately 2 to 3 gallons, or 7.5 to 11.5 liters, of antifreeze should be enough to fill the RV’s entire plumbing system, given that a bypass is installed. If you don’t have a bypass valve installed, you’ll need as much antifreeze as the water heater can hold, which is usually 6 to 10 gallons.
  • Place the disconnected end of the water line in a jug of RV antifreeze. RV antifreeze should be pink in colour, which means it is GRAS and generally regarded as safe. The green antifreeze is toxic and not recommended.
  • Turn on the fresh water pump, and allow it to run as it pulls the antifreeze into the plumbing system of the RV. Alternatively, use a hand pump connected to the city water hookup.
how to winterize RV's plumbing system
A map of your RV’s plumbing system.
  • Start from the highest to the lowest point in the fresh water system, that is you’ll probably start at the kitchen sink. The general order is kitchen sink, bathroom sink, shower, toilet, and outdoor shower. 
  • Turn on the sink’s hot faucet and keep it running until the water turns pink, that is all the water has been flushed from the system and it is now filled with antifreeze. Then, run the cold faucet until it’s also pink.
  • Move on to the lower points in the fresh water system until you see each flowing out pink fountains.
  • You may need to flush the toilet several times until the RV antifreeze comes out steadily.
  • Pour about 3 cups (0.72 liters) of antifreeze into the toilet and in each drain, including the washing machine, ice maker, and outside shower. 
  • Now that you’re done, take the water line out of the antifreeze jug, and reconnect it to the fresh water tank.
  • Locate the water heater, remove the plug and drain it. Note that this step must be done last.

How To Winterize An RV: Other Things To Do Before Winter

After making sure your water lines will not freeze and burst during the extreme cold months, there are other places that need to be taken care of, so that you will find your rig in good condition after winter is over.

Cover all vents and holes

Hopefully you already have some type of mesh guard for your exhaust pipe to protect against mice. Now make sure all the vents and holes are covered. 

Check the entire RV for other places that bugs or animals may be able to get into. Birds, rodents, or bugs can inhabit your RV on the roof, pipes and seams to hide from the cold. 

Clean and seal the exterior


One area that is usually neglected is the rubber roof of your RV.  After a full summer of parking under trees, road grime, and the sun baking it, your roof needs some repair.

The general process is as follows:

  • Clean with a special rubber roof cleaner. A popular choice is the Dicor Corporation RP-RC-1GL Rubber Roof Cleaner Gallon, which costs $22 and receives a 4.5 star rating on Amazon. Scrub it with a soft brush and the cleaner and then rinse with clean water.  
  • Repair lap sealant to create a secure, secondary seal along the roof’s edges, air vents, vent pipes and screw heads. A good choice for sealant is the Dicor 501LSW-1 Epdm Self-Leveling Lap Sealant, which costs $10 for a 10.3 oz. tube and receives a 4.7 stars rating from almost 2,000 reviews on Amazon.
    Water damage is one of the most common problems for RV’s.  Touching up the lap sealant is a great way to prevent water from getting in. Look for any cracks or missing lap sealant around all of the protrusions in your roof.  Anywhere you see something that looks questionable add some self-leveling lap sealant.
how to winterize a travel trailer
Apply roof sealant.
  • Seal with a rubber roof protection product to help keep the rubber clean and protect it from the sun. Dicor Corporation also offers the much loved RP-RG-1GL Rubber Roof Protectant, which costs $28 for a gallon and receives a 4.6 stars rating on Amazon. 

The sides

The walls of your RV also need a good scrub and protection from the elements.  For this step, just use your favorite RV or car wash and a wax that is easy to apply. Your RV has an enormous surface so you don’t want a wax that takes a lot of buffing.

Cover it with a breathable material

To finish off, it is best to invest in a durable and breathable RV cover to protect your precious RV from rodents and mice and whatnot, while preventing mold and mildew to grow underneath your tarp. 

To better maintain your cover, you may want to put rags on top of the sharp corners of your RV so that the cover doesn’t rip. 

About Chris Coleman

Chris Coleman is an interesting travel blogger and outdoor photographer with a great sense of humor. He owns an RV Accessories shop in New York City so he has the knowledge necessary to provide thorough reviews and give advice on how to choose the right products for RV travel. He puts all that RV knowledge and experience to good use in his sharing posts. Besides product buying guides/reviews, Chris also writes informative articles, how-to articles and RV camping guides in his own interesting viewpoint. Chris’s blog is one of the most reliable information sources for RV campers no matter if you're an expert or a determined beginner.

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