The Great Ways to Insulate Your Trailer

If you remember my recent article on preventing premature battery death, much of the information available on the web is for recreational vehicles, not trailers. It’s a bit of a shame, because they are two different vehicles with often different needs.

For example, a motorhome or RV is often equipped with a heater and / or an air conditioner to control the temperature. Trailers, especially the smaller ones, do not always have this equipment. This is why it is all the more important that your caravan is insulated from top to bottom. That way you can trap the heat or the cool and keep it as long as possible.

But if you did some research on insulation, you would only find solutions for caravans. This does not mean that these same solutions will not work for your caravan, as some will.

It is time that caravan owners get the recognition they deserve. This is why, in this article, I am compiling five great ways to maintain the temperature in your caravan through insulation. While not all of these methods are for trailers only, most of them are.

Before I start, there are two things I want to note. The first is that it is not recommended to spend the winter camping in a caravan, even if you use all the insulation methods I suggest. Caravans are prone to air leakage and may have a single thin layer of insulation, often fiberglass. These factors work against you.

I would also like to quickly explain what an R-value is, as it will increase a lot. The more effective the insulation is to maintain a uniform temperature, the higher its R-value. The insulation will be better or worse depending on the climate in which you live, at least as far as the insulation of the house is concerned. All of this is fascinating, and here you can see a graph that divides the country into several areas.

Since you are isolating a mobile vehicle, you don’t need to worry as much about the difference in R-value between the country and the different areas. Just know that the higher the R-value, the better.

Well, without further ado, here are five ways to insulate your caravan.

  • Replace your windows

Most trailers have single glazed windows. These do not isolate your vehicle at all, and even do the opposite. Single glazed windows are thin and inexpensive, so cold or hot air can easily enter the trailer through the windows. It makes you shiver or sweat.

You then have two options. The first and best is to completely replace the windows. But there are several reasons why you might be reluctant to do so. First of all, it can be quite expensive. Second, tinkering with your caravan at this point could void your warranty.

I understand your reluctance. This is why I will also tell you how to insulate a single glazed window. It won’t be as great as replacing windows, but you should notice a difference.

Replacement of windows

Step 1: Start by measuring the size of the windows of your caravan. You may think they are standard size until you arrive at a DIY store and quickly realize that none of the windows will suit you. It would be boring (and potentially dangerous) to get a poorly adjusted window and have to cut it yourself. Be sure to order the correct window size the first time.

There are generally four choices for caravan windows: awning windows, vertical runners, horizontal runners, and louvered windows. Now let’s look at each type of window:

Awning windows: Awning windows are a good choice for medium-sized trailers, as they only have double opening windows.
Vertical slides: As their name suggests, the vertical slides are high. They also open with a slide on rails.
Horizontal slides: The horizontal slides are therefore identical to the vertical slides, but they open on the side.
Windows with jealousy: Finally, there are jealousies. With a poor seal but a magnificent view, the shutters are a compromise.
Step 2: Once you have ordered and received your new windows, you can begin to uninstall your existing windows. Sometimes you just have to unscrew the window frame and go ahead. For metal and vinyl siding windows, you will need to remove the siding first.

Step 3: Scrape off the leftover putty or caulk.

Step 4: Put the window in place, using fresh putty to hold it in place. It is recommended to buy new screws and siding so that the windows insulate better.

Window insulation

If you don’t or can’t make the effort to get new windows, you can always isolate what you have. Here are some tactics to try:

Apply plastic insulating film: For a few dollars, you can get a plastic insulating film. You cover the window (on both sides), then use the supplied double-sided tape to hold the film in place. Then you use a hair dryer to seal the film tightly. It’s not the best thing, but it works.
Wrap the windows in bubble wrap: If you don’t really care about the look, then bubble wrap is your friend. You will need a spray bottle filled with water, which you will spray inside and outside the window. This should give the bubble wrap something to hang on to.

  • Close the doors

Now that your windows are cared for, it’s time to tackle another area where significant heat / cold loss occurs: your doors.

If the doors of your caravan are not fitted with weatherstripping, this is the first thing you can change. You can order weatherstrips online or buy them at any DIY store. If you are a homeowner, you have seen wipers in action. This band of bulky fabric sticks under your front door to prevent air from drafts from disturbing the freshness or heat of the interior.

A door snake has the same function as the weatherstripper and can be made as easily as taking a dish towel, rolling it up and putting it under your door. Again, does it look good? No, but if you’re inside for the night, who cares?

The last method is longer because it is a DIY job. This involves reapplying a new layer of sealant around the doors of your caravan. You should do this at least once a year (or about every two years) anyway, so it’s good to get used to it now. If you notice holes, cracks or small spots, add additional sealant. This should reduce drafts.

  • Cover your vents

If you have insulated your windows and doors and you still notice cold or hot air entering your caravan, you may have forgotten your air vents. After all, they are higher up in your vehicle, so it’s easy to miss them.

The air vents of your caravan are a crucial element of your installation, because they allow moisture to circulate and leave your vehicle. This helps prevent unpleasant fogging in the short term and mold in the long term.

That said, your air vents can also keep you from staying cool on hot nights and make your teeth chatter in cold weather. The solution ? Get a ventilation cushion!

This one from Camco is essentially the best of the best. It is rated five stars on Amazon and is also an Amazon Choice product. It costs $ 14.99, so it shouldn’t break a budget. It is designed for recreational vehicle and trailer vents of at least 14 inches, but you could probably cut or compress it to fit smaller vents.

You can get the ventilation cushion with or without a reflective surface. The non-reflective cushion is a little more expensive, under a dollar. Both types of cushions will more effectively insulate your caravan. The reflective version even offers additional UV protection.

Obviously, you should not use the vents on your trailer while the cushion is still in place. It is so easy to put on and take off this cushion when you need it that you will wonder how you ever lived without it.

  • Bypass the trailer

It is true that baseboards are a tactic used more for caravans than for trailers, but good! What prevents you from doing the same with your vehicle? After all, the underside of your caravan is just as vulnerable to chills or outside heat as that of a motorhome.

Let’s rewind for a second. You are probably wondering what exactly is a skirt? It is a layer of fabric that you wrap around the bottom half of your vehicle and hangs from the ground. The skirt prevents excess cold or heat from entering under and into your trailer. In addition, it’s pretty cute, I must say.

As I mentioned, it is much, much more common for caravans to have skirts than trailers. So you will probably have to settle for buying a caravan skirt and tailoring it to the size of your vehicle. specializes in the design of skirts for recreational vehicles. If you have a fifth wheel caravan, you can get a specific skirt for this type of caravan. Otherwise, you can contact them or another manufacturer and inquire about the custom dimensions.

Why get a skirt for your caravan? According to TripSavvy, a skirt can control the interior temperature in an exceptional way. You can reduce your propane consumption during the colder months, because you don’t need as much fuel to keep your vehicle warm.

  • Re-insulate the walls

Remember at the start of this article that I mentioned that most trailers have a thin layer of fiberglass insulation on the walls? Yes, it is not good. Even if you apply the other four isolation tactics I suggested, you may not be as comfortable as possible.

By re-insulating your walls, you can be sure that you have done everything you can to control the temperature in your caravan. I should warn you that doing this work yourself will likely void any type of warranty you may have. You may want to check with the manufacturer of your trailer if even a professional can work on your walls.

Once you have fixed this problem, you can choose from several insulation materials. It is

Spray foam: For a simple DIY job, aerosol foam is ideal. Not only does it have a relatively high R-value (I told you it would happen again), but it comes in a box or similar container. Then you apply it using the canister. The aerosol foam is in the form of a shaving foam. Once you let it settle, your walls are now much better insulated.
Rigid foam: Then there is the rigid foam, which you can size just right by cutting it out. This pink foam also has a good R value. You will need industrial tape or caulking to adhere the foam to the walls of your trailer. Rigid foam is known for its strength, durability and moisture-fighting properties. Although it sounds easy, it is a lot more difficult work than using spray foam.
Fiberglass foam: Instead of replacing the insulation you use, you may be able to add more. After all, fiberglass foam is not that bad. It has a good R value and is able to keep the fresh air in the vehicle during the summer. Expansion occurs when the fiberglass heats up, so you will need to change this insulation every two to three years. Another drawback is the risk of mold in the insulation. You will feel it before you see it, and by then it will be too late to recover it in most cases. You will then have to change the insulation.


Caravans may have more layouts than trailers (most of the time), but that doesn’t mean that you have to go through your fall in freezing cold or that you have to sweat all summer. There are many ways to better insulate your caravan.

Start with doors and windows, two of the biggest culprits. Air vents can also let outside air into your temperate caravan. Finally, if none of this works, I recommend that you consider re-insulating the walls.

Of course, trailers aren’t necessarily designed for winter driving, but with new insulation, you know you can handle almost all of the extreme temperatures that the weather has in store for you.

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