Winter RVing
February 23, 2001
© 2001 Arthur G. Knapp. All Rights Reserved.

For most RVers, RVing is a way to avoid the winter. We use our RVs to follow the sun and stay in "snowbird" areas such as Florida, Texas, Arizona, or California. The end of fall signals the start of an annual migration of thousands of RVers to the south and the west. Our goal is to avoid the winter slush and cold. However, some RVers, either by choice or by circumstance, end up living in their RVs in cold weather areas. This article is for both those RVers who "got left behind" and those that choose to seek out cold weather camping.

The Benefits

There are benefits to cold weather RVing. You will not have to contend with mosquitoes, and there will be fewer other insects to deal with. Because most RVers have headed to warmer areas, there will be less competition for available spaces, and the spaces that are available should be at the off-season rates. Some activities such as skiing (downhill or cross-country), snowboarding, snowmobiling, hunting, ice fishing, or snowshoeing require being in cold weather locations. And finally, the beauty and serenity of a winter landscape is hard to surpass.

Planning Ahead

With careful planning and preparation, your RV can be an enjoyable way to live in or visit the many beautiful winter areas accessible by RVs.

If you need to travel in order to get to your winter camping spot, be sure to reduce your driving speeds and allow yourself plenty of time to get to your destination during daylight. It is a good habit to check the weather forecast for the area you are traveling through and to call the Highway Patrol for any road condition or weather alerts. Before leaving, make sure your RV is properly prepared for the cold you are going to encounter. Your cold weather RVing experience will be warmer and less stressful if you are properly prepared.

You should anticipate driving in icy, snowy and windy weather. Make sure your windshield wipers are functioning and that the wiper blades are in good condition. Check the condition of your tires. Check your antifreeze protection level to make sure it is low enough for the area you are going to visit. If you are driving from a warm area into a cold area you may need a fuel additive in order to avoid jelling of the diesel fuel at low temperatures (in cold weather areas the additive is already in the fuel). Check your heating system to make sure that it is functioning properly. (You don't want to arrive in minus 10 degree weather and find out your furnace won't light). Fill your propane tank before departing.

Batteries do not function well in cold weather. (At 0 F, the useable amp hours of your batteries will be about half of their rated capacity). Check the condition of your batteries. Replace batteries as necessary before starting your trip.

If the weather will be below freezing when you start out on your trip, it will help if you turn the furnace on in your RV a full day before you leave. This will give the furnace time to preheat the interior of your RV and provide a more comfortable trip. Also, when you arrive at your campsite, it will be much easier to maintain the temperature than to heat up a cold RV.

Just in case something goes wrong, be sure to pack plenty of blankets, at least a gallon of bottled water (per person) and a cell phone.

Getting Warm

Heating an RV in severe weather is different than heating one for more moderate temperatures. In moderate temperatures (above freezing), properly vented catalytic heaters may be all you need. (I would not go to sleep with an unvented catalytic heater, even if it had an oxygen sensor shutdown). However, catalytic heaters are not appropriate for temperatures below freezing. Too much ventilation is required to avoid water vapor buildup and oxygen depletion.

A properly operating propane furnace or a diesel-fired hydronic heater is required for cold weather RVing. Most RVs are designed with furnaces for a moderate climate. If you are living in cold weather or visit cold weather areas often, you may need additional heating capacity. A rough formula for computing your minimum heater requirement is: temperature difference (T), times wall area of the RV (A), divided by R value of the RV insulation, divided by an efficiency factor for the furnace (.60). For most RVs with single pane windows try R3 for the insulation factor. For RVs that follow the advice in this article, try R6. The wall area will be approximately equal to length times 29, plus 100 (for a 32' RV this computes to 1028). If you want to be able to maintain 60 degrees inside when it is minus 20 outside (80 degree temperature difference) and you have a well-insulated (R6) RV that is 32' long, you would need a furnace or furnaces rated at a minimum of 22,844 BTU/hr. (80*1028/6*.6=22,844).

Electric space heaters or ceramic heaters can be used as a supplement to your furnace, but not as a substitute. Never attempt to heat your RV with the propane oven or stove.

Keeping Warm

Some RVs are built with cold weather in mind. These RVs will have better insulated walls and ceilings, and perhaps even insulated floors. You will find that they have double pane windows and heated bays. The entire plumbing system is kept heated by engine heat while driving and by the RV heaters while camping. Having an RV designed for cold weather use is an advantage, but not a necessity. There are many things that you can do to improve your ability to stay warm in most RVs.

To begin with, don't try to keep your RV heated to 75+ degrees. Consider setting the thermostat to 62 degrees during the day and 50 degrees overnight (letting it get too cold at night will just cause a problem heating it up the next day). To compensate, use cold weather clothing (layered) during the day and evening, and plenty of blankets at night. Some people like to use electric blankets.

If you will be staying for more than a few days, consider "skirting" your RV. This will cut down on the heat loss through the floor and will keep the cold winds from blowing under the RV and right up through your floor. You can purchase professional skirts for many RVs, or you can use a simple system we have used for years. Purchase some heavy mil plastic (in rolls) and some duct tape. Tape the plastic to the RV. The wrap should go all the way around the RV and drop to the ground with enough extra material at the bottom to allow you to place rocks or boards on it in order to keep it on the ground in case of winds. Try to park the RV to take advantage of morning sun.

Insulate your windows. You don't have to spend thousands of dollars for double pane windows. You can buy inexpensive plastic windows that will Velcro in place. Or, there are products available that use a thin plastic material that you tape and heat shrink to the window.

If you have heavy drapes that will cover the windshield, use them. If not, consider hanging a blanket or quilt between the windshield and the living area.

Your skylights and roof vents are an escape hatch for warm air. Purchase insulating covers for them or make your own. We use 4" foam rubber and cut a piece to size so that it will fit snugly in place.

RV doors are not only a good way for you to get in and out, but are a great way for cold to get in and warmth to get out. Keep the door open as little as possible. Check the door for obvious gaps and fix the gaps with insulating tape or sealant. You can even make a door cover that will attach to the door using Velcro.

If you are really serious about it, make a thorough inspection of your RV bays and undercarriage and fill any cracks or holes with caulking (plumbing and electrical are the major areas).

The Plumbing

If your plumbing compartment is not heated, you will need to run a furnace vent to the compartment, or purchase an electric space heater (with thermostat) to install in the plumbing bay. If you will be doing considerable driving in freezing weather or boondocking, you will need to provide a heating source that uses propane or diesel fuel to keep the bays heated. Our RV uses hydronic heating (hot water passing through a "heat exchanger") provided by the engine cooling system to provide heated bays and hot water while traveling.

Our experience is that even with heated bays, severe temperatures (below minus 10 degrees) require additional effort to avoid freezing of water within the plumbing system. Any part of the plumbing system that is not inside the RV should be wrapped with electrical heat tape and then covered with pipe insulation. Pay particular attention to the water pump and lines entering and exiting it. If you are using heat tape on plastic plumbing, make sure you use a heat tape designed for that application.

To prevent holding tanks from freezing, you can purchase heating pads for the tanks. Ultraheat sells one that is thermostatically controlled (on at 44 degrees, off at 64 degrees). They will run on 12 or 120-volts. These units will keep the contents of exposed gray and black water holding tanks liquid at wind-chill temperatures of 20 degrees below zero. In addition to the tanks themselves, you can heat the sewage lines leading from the tanks by adding pipe heaters (available from Ultraheat) or by using heat tape. As an alternative, nontoxic antifreeze can be added to the black or gray water tanks to prevent freezing. However, be sure to add additional antifreeze as more waste is added.

When hookups are available, it is best to keep the sewage tank valves closed, and dump the tanks when they are near full. Add at least 5 gallons of water after dumping. We prefer not to leave the water hose connected. We use water from the fresh water tank until it is about ¼ full, then we refill it. If you choose to leave the water hose attached, make sure it is well insulated. Also, we do not leave the sewer hose connected. We attach it only when we are dumping. If you choose to leave it attached, make sure it is heat wrapped or well insulated (or both).

Cold Weather Boondocking

Many RVers prefer "boondocking" (camping without hookups). Frequently hookups will not be available near your favorite ski resort, fishing hole or hunting spot, so boondocking becomes a necessity. Under the best of conditions, boondocking is challenging. In cold weather it is something only the hardy or the foolhardy should attempt.

As in warm weather boondocking, the battery is frequently the limiting factor. In cold weather camping, your battery capacity can easily by reduced by 50 percent. Also, the battery voltage may be a volt higher than in warmer climate use. Because of the higher battery voltage, your battery charger may not fully charge the batteries. Even more than during warm weather boondocking, additional batteries can be a way of extending your stay. Keeping your batteries warmer will increase their usefulness, but never keep your batteries inside the RV or in an unvented location.

The charging capacity of your inverter/charger or other charging source should be at least 20 amps, preferably more. Some battery chargers are adjustable to compensate for temperature differences. If you will be doing a lot of cold weather boondocking, they are highly recommended.

The refrigerator (even when operating on propane) uses a substantial amount of battery power. When camping in near freezing or below temperatures, consider turning the refrigerator off, at least overnight. You will be surprised how cold items will remain.

Because of a lack of available power, heating the plumbing bays or using a tank heater may be impractical. In this case, I suggest that the fresh water system should be winterized with antifreeze before leaving home. Water for drinking and cooking should be stored inside the RV in plastic containers.

I do not recommend leaving the gray water valve open (some do). Even a small accumulation of water can freeze and block the sewer line.

Propane will liquefy (and therefore no longer work in your RV) somewhere around minus 44 degrees. Propane tanks are not in enclosed bays, so are more susceptible to the elements. However, we have spent weeks in weather at minus 25 degrees with the wind chill reaching minus 50 degrees, and never had a failure of our propane system.

Combating Moisture

Unfortunately, along with winter RVing comes an excess of moisture. It can cover the windows, run down the walls, accumulate in closets and dampen clothes and bedding. This water comes from the difference in outside and inside air temperatures, cooking, showering, catalytic heaters, and just plain breathing. (During the winter, we lose more water from our bodies than usual. We need to be sure to drink plenty of water to avoid dehydration).

In order to make heating the RV and maintaining the heat easier, we have insulated it. This is directly at odds with trying to reduce condensation. The same airtight, well-insulated RV that is desired for maintaining heat can cause the condensation problem. Since the large amounts of moisture that we generate through normal living (washing, breathing and cooking) can't readily escape through the walls or around sealed doors, it instead becomes liquid (or freezes) on contact with cold surfaces like window glass or metal window frames.

The easiest way to combat this water vapor or condensation is through the use of a portable dehumidifier. However even without a dehumidifier, there are steps that can be taken to reduce condensation.

Double pane windows (as discussed earlier) are a big help. Even using the acrylic or shrink-wrap windows will help. This protective layer of plastic film insulates by forming an air pocket and (as a fringe benefit) keeps the moist inside air away from the cold windows, decreasing condensation. Of course, these are not intended to be permanent, do not open and will have to be removed in the spring for ventilation.

Make sure that all roof vents (refrigerator, stove, bathroom) are free of snow and debris so that they can allow proper ventilation. At night, it is a good idea to leave a roof vent or a window partially open. Leave cabinet and closet doors open to allow for better air circulation.

Conclusion

Winter can be a spectacular time to go camping, even in the more severe climates. Winter camping in an RV is not for everyone. However, those that choose it can increase their chances of a pleasant time by having proper advance planning and the right equipment. Winter camping requires special attention to heating and insulation matters, knowledge of power requirements, and proper ventilation. Drive safely and enjoy!