(9 Steps) How To Insulate A Travel Trailer For Winter Use

If you’re still making payments on your RV, you aren’t allowed to stop making them once the cold weather rolls around. So why not take the extra steps to insulate the camper so you can use it all year long? In this guide, we’ll tell you all you need to know about how to insulate a travel trailer so it will be functional for four-season use.

1. Check The Specs

It’s too late for this step if you’ve already purchased the camper, but if you’re still shopping, look for a unit that’s relatively compact. The less living space the trailer has, the easier it will be to keep it warm. Plus, it won’t take nearly as long to perform all the routine maintenance that we’re about to get into.

When you find a camper you’re interested in, enter the year, make, and model into an internet search engine. From there, it should be easy to check the specs. Travel trailers that measure under 25 feet in length are preferable, but depending on the size of your family, you might need to go a bit larger.

2. Seal The Windows

Windows are the first line of defense when it comes to cold-weather camping. Unless the unit is equipped for four-season use, it’s probably outfitted with single-pane windows, which offer very little protection. In addition to letting the cold air in, they allow heat to seep out through the glass, opening up a two-way avenue for heat loss.

Some class A and class C motorhomes offer double- or triple-pane windows. These are thicker but not necessarily more durable—excessive vibrations can cause them to crack. They also cost more money, whether it’s a new installation or a simple replacement. For these reasons, we wouldn’t recommend replacing the windows unless the ones you have are already damaged.

Instead, inspect the caulking around the frames and reinforce any spots that have suffered undue wear and tear. Then use bubble wrap secured with double-sided tape to cover the camper’s windows. This provides you with a layer of insulation without interfering with the natural light—an important consideration in any season, but especially in winter.

Finally, consider swapping out your usual curtains for insulated ones. Solar curtains, which can be configured to reflect the heat back toward the interior, are another option.

3. Secure The Doors

Once you’re finished with the windows, you can turn your attention to the exterior doors. Check the weather stripping and test the surrounding area for drafts. If the draft is minor, you might be able to get away with plugging a cloth “snake” along the base of the door or hanging a thermal curtain in front of it. Should you decide that you’re better off replacing the door altogether, make sure to invest in one with an energy-efficient rating.

Don’t neglect the doors that lead to storage compartments, either. Use weather stripping and seal them as you would any door. If they’re located on an exterior wall, you can place a layer of insulation toward the rear to prevent cold air from whooshing in every time you open them.

4. Go From Top To Bottom

Starting at the ceiling, look for any spots that might allow heat to escape. If you have a roof vent, invest in a quality vent cover. Don’t forget to take the cover off when you’re cooking (see #9: On The Road, below). As a precaution, make sure your smoke alarm is in good working order.

When you’re parked, you can use an insulated tarp to cover the trailer. Be careful not to block every opening—the RV will still need proper ventilation. The extra insulation might cause excess moisture to collect inside the camper, so you might want to set up a dehumidifier to prevent mold from forming.

Once you’ve got the roof and ceiling covered, take a look at the floor. Add cushions or skirting to any areas that are prone to drafts. If your floors aren’t carpeted, consider adding a few throw rugs to the high-traffic areas.

5. Secure The Perimeter

Depending on the model, most RVs are equipped with either foam-insulated or fiberglass walls. Fiberglass is considered superior when it comes to maintaining interior temperature, but it still might not provide enough protection in the winter.

Check the specifications again to determine the R-value of your camper. R-value is the term used to describe thermal resistance, so the higher the number, the easier your job will be. As a rule of thumb, the range for camper trailers runs from about 5 to 20.

If there are areas on the wall that have been exposed due to snipped wires, give them a quick dose of spray foam. You can also add a whole new layer of fiberglass insulation, but this is a costly and tricky procedure that might require the aid of a professional.

A word about slide outs: These extensions are noticeably ill-equipped for cold weather. We would recommend reserving their use for the spring and summer months. If you really need the extra space, one option would be to affix a few foam boards to the base of the slide out, then remove them once it’s time to pull the slide back in.

Also, note that any alterations you make to your camper—including the addition of extra insulation—might void any existing warranties. That might not be a concern if you’ve owned the camper for a while, but if this is your first year with the unit, make sure you understand the consequences before you proceed with the winterization.

6. Attach The Skirting

Skirting represents another way to keep camper warm. It involves affixing a layer of material to the perimeter of the trailer. When you’re done, it will look as though the camper is wearing a skirt, hence the name.

You might be able to find skirting that’s designed specifically for your camper. Do a Google or Amazon search to find out if it’s available for your make and model. If the search comes up empty, generic versions are also available.

Take a look at the exterior walls of your travel trailer, toward the bottom. There should be a rail that runs along the entire perimeter, known as the “channel system.” Slide one end of the skirting material into the channel and continue feeding it through the system until the base is thoroughly covered.

Some rigs might not have a channel system. For these, you’ll need to use buttons or T-snaps, available at most camping retail outlets. This is a carefree and popular method, but it doesn’t create as tight a seal as the channel system.

Once your skirting is in place, use weights or additional foam boards to attach it to the ground.

For more tips on skirting, take a look at this video tutorial.

7. Protect The Pipes

If your pipes freeze, that’s the end of your winter camping adventures. If you want to properly insulate a travel trailer, it’s imperative to protect those pipes.

Apply 110V heat tape to your freshwater hose, taking extra care with the spot where the hose connects with the camper. Give any valves and connections the same treatment. We would recommend using foam insulation on the hoses as an added precaution.

Fill the internal freshwater tank before setting out. If you can use your own water supply instead of connecting to an outside source, you can disconnect the freshwater hose completely so it can be stored until the weather warms up again.

At night, you should open the bathroom and kitchen cabinets so the internal pipes will be warmed by the ambient heat. Additionally, turn your faucets on to allow a small amount of water to run through the pipes.

8. Safeguard The Septic System

To keep your holding tanks from freezing, pour in a small amount of non-toxic antifreeze. You can tell which types are non-toxic by the color, which is pink rather than bright green. When in doubt, check the label.

Don’t be tempted to dump your tanks before they’re nearly full. Dumping them too early will increase the risk of freezing. Also, remember to always secure the waste valves when you’re not using the tanks.

Finally, you should surround the holding tanks with a box fashioned out of plywood and fiberglass insulation. Special heating pads are also available for this purpose.

9. On The Road

If “Keep Camper Warm” is your primary goal, there are other steps that you can take once you’ve reached your destination.

First of all, be sure to dress warmly, paying particular attention to the lower regions. Long johns and heavy socks will keep out any lingering drafts and make you feel even cozier.

Second, don’t shy away from the kitchen. When you cook up rich, hearty meals like beef stew or macaroni and cheese, you’ll boost the ambient temperature without even trying. If your camper has an oven, you can expand your repertoire even further.

Another option is to purchase a space heater for the area you’ll be using the most. These can be a godsend in colder weather, and they’re relatively inexpensive. As always, make sure the space is properly ventilated, and that you have a working carbon monoxide detector in place.

The Bottom Line

In short, there’s no need to put your travel trailer up on blocks when November comes calling. By taking these simple steps to insulate your second home, you can have a superb cold-weather camping experience.

Best of luck, and happy camping!

Check out our article on: (10 Steps) How To Winterize An RV Or Camper For Safe Storage

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