RV Window Insulation Tips for Summer and Winter

Sharing is caring!

Thanks for your support! If you make a purchase using our links in this article, we may make a commission. And, as an Amazon Associate, I earn from qualifying purchases. See the full disclosure here.

Summers can bring scorching heat, making the inside of your RV feel like an oven. Cold weather can make sitting in your camper a bone-chilling experience. One step you can take to help you meet the challenges created by extremes in weather is to improve the insulation in your RV. An excellent place to start is with our RV window insulation tips for summer and winter.

Most trailers have single-pane windows. And, one of the most significant sources of heat loss for your RVs is these same single-pane windows. While glass is a reasonably good insulator, a single-pane window does not contain enough glass to do the job. However, single-pane windows are easy to manufacture and inexpensive to install, and this is why trailer manufacturers use them.

With single-pane windows, the heat loss in the winter and heat gain in the summer will cause you to be uncomfortable in your camper. You will experience higher heating and cooling costs, not to mention the wear and tear on your RV’s heating and cooling systems.

You could certainly replace the single-pane windows with double-pane windows. There are several reasons you might not want to do that. The first is that it could be expensive. The second is that modifying your trailer to that extent could void your warranty.

There are several other options for insulating your RV’s windows available to you that can work well, provide flexibility, and are relatively inexpensive.

How Does RV Window Insulation Work?

Window insulation products create a barrier to help prevent heat loss in cold weather. They can also help prevent heat gain in hotter weather. Insulating your RV’s windows against heat loss or gain will help you stay cooler in the summer and warmer in the winter.

Also, moisture in the RV can condense on colder window surfaces. This condensation can lead to mold or mildew problems as well. Two ways to decrease the humidity in your RV is to either lower the moisture level by using a dehumidifier or increase airflow. However, increasing airflow can create other issues depending on current weather conditions.

The main point here is that, if your single-pane windows feel cold to the touch, that means heat is escaping through them. It also means your RV probably feels drafty and your heating costs are going to be higher. So, let’s take a look at insulating those drafty RV windows.

Should the RV Window Insulation Go on the Inside or Outside?

Deciding if you should place the window insulation on the inside or outside of your RV windows often depends on what you are using to insulate the windows. If you are using insulated RV window curtains, placing them on the outside would be silly at best. However, one of the most effective ways to improve insulation for your windows is to use bubble wrap with a layer of foil (also known as Reflectix) on either side.

Placing the Reflectix on the inside of your RV windows, especially when it’s scorching hot outside, can cause the window to heat up to the point of cracking. The best way to prevent your RV’s windows from heating up is to place this type of insulation on the outside. Placing window insulation such as this on the inside can also contribute to condensation problems.

Homemade RV Window Covers

Bubble Wrap RV Window InsulationHomemade window covers are another great way to insulate your RV’s windows against heat loss in the winter or to keep heat out in the summer. An excellent window cover would be the combination of Reflectix and bubble wrap mentioned earlier and recommend for use on the outside of your RV’s windows.

You can also use bubble wrap by itself on the inside. To insulate a window with bubble wrap, dampen the glass and stick the bubble wrap to it. The bubble side of the wrap will be facing the glass. Just try to find bubble wrap that comes in 24″ wide rolls rather than 12″ or you will find yourself taping the bubble wrap together to cover most of your windows. Also, make sure the bubble wrap is at least 5/16″ thick. The thicker the better.

Use a spray bottle or a damp rag works to moisten the window. Adding a little dish soap will help the bubble wrap stick even better. This method requires you to keep the bubble wrap on the windows all winter. However, if it comes loose, you can dampen the glass again and stick it right back up. You can also use clear tape to tape two or more pieces of bubble wrap together for bigger windows.

An advantage of using bubble wrap alone is that it still lets light through the window. However, seeing clearly through the window is out of the question.

How to Make Insulated RV Window Curtains

DIY RV Window Insulated CoversAnother low-cost way to help insulate your RV’s windows is to make insulating RV curtains. Making these curtains is also relatively simple if you are handy with a sewing machine. To get started you will need some good quilted material such as a mattress cover for the exterior layer, an inexpensive liner material such as sheets for the interior layer, and heavy-duty aluminum foil for the middle layer.

First, measure windows to determine the curtain sizes. Then use the mattress cover for the outside layer, the foil for the middle layer, and the liner or sheet for the inside layer. Bind them all together. Also, you can use a foil tape like that used by HVAC companies use to attach foil or Reflectix for larger windows. If you want to get fancy, use a carpet edge tape to cover the outside edges giving your curtains a more finished look.

The insulated RV curtains can be hung between the blinds and the window, and will significantly reduce heat loss in cold weather as well as help keep the heat out in the summer.

Plexiglass RV Window Insulation

Plexiglas window covers can be an excellent choice for larger windows. You can purchase plexiglass sheets from almost any building supply store. Plexiglass is easy to cut with a utility knife, and you can use clear acrylic mounting tape or even Velcro to hold it in place.

Plexiglass covers allow for the critical insulative air space, while still allowing an unobstructed view through the windows. However, plexiglass can be a bit more expensive than other options, costing in the neighborhood of $45 for a 0.080″ x 24″ x 48″ sheet.

Shrink Wrap Your RV Windows

Another possibility is to use a window insulator kit. These are the same heat-shrink plastic kits people use to insulate their windows at home during the winter. Essentially, you place a double-sided tape (typically included in the package) around the window frame. You then cover the window with plastic by sticking it to the tape.

Using a hairdryer, you heat the plastic which shrinks, causing all of the wrinkles to smooth out. The tape forms a seal around the edges, trapping a layer of air between the plastic and the glass. Again, it is this layer of air which provides insulation against the cold, helping you to stay warm.

Reflectix for RV Window Insulation

Another popular choice is to cover your RV windows with Reflectix. Reflectix has excellent insulative properties. However, if sunlight is key to your sense of well-being, this may not be the best option for you. As its name suggests, Reflectix reflects the sunlight away and will not let it through.

Reflectix may help insulate your RV, but it also repels a useful source of heat in the colder weather, that source of heat being the same sunlight mentioned above.

Because of this, many RVers put Reflectix in their windows at night and take it out during the day. Removing it allows the sun to warm the RV during the day. The problem here is that you have to take it down and put it back up daily. Also, sitting next to a single-pane window on a cold day can be a drafty experience. Some of those methods mentioned above may be better methods for insulating your RV’s windows.

Can RV Window Tinting Help Insulate an RV?

Tinting your RV windows can certainly help to keep the heat out in the summertime. In fact, some of the more advanced window films can help to keep heat inside your RV too. For much more information about how tinting your RV Windows can help insulate your RV check out our helpful article called RV Window Tinting – Increase Privacy and Reduce Heat.

RELATED READING: Check out our artcile How Long Does an RV Propane Tank Last (Heat, Fridge, Water) for a deep dive into propane use.


As you can see, there are many ways to insulate your RV’s windows. These different options range from simple and cheap to more expensive and complicated. Some may actually be quite fun for the handy do-it-yourselfer.

Adding an insulation layer to your RV’s windows can significantly increase the comfort level in your RV while also reducing your heating and cooling bills. It can also reduce the wear and tear on your heating and AC system, prolonging their service life.

And, you can utilize many of these options full-time, keeping your RV’s comfort zone on your open-road adventures much more consistent.

Do you have some creative ways you have insulated your RV from hot or cold weather? Please share your comments below! We would love to hear from you!

For more related information check out some of our other helpful articles below:



Sharing is caring!

7 thoughts on “RV Window Insulation Tips for Summer and Winter”

  1. What is one of the best dehumidifier for my 32 foot travel trailer? Need one now?!!

  2. How do you attach the reflextix to your camper windows on the inside.???

  3. I want to have plexiglass put as a second barrier for my windows. I saw where they used magnetic tape to secure it to the windows and want to do that. I would like your opinion on that. Also, do you get condensation between the window and the plexiglass if there is a good seal? If so how do I prevent that?

  4. I have installed Reflectix on several of my 5th wheel windows recently, and am amazed in the results of keeping the heat in. Especially the the 2 windows next to the bed. I actually covered the whole wall behind the bed and it made a huge difference. My only problem is I was hoping it would eliminate the condensation, especially on the door windows, which runs down the inside of the door and starts to rust out the bottom. Do you know if I have installed it wrong or does it not stop the condensation? I only used 6 squares of Velcro to secure onto the window frame and not sealed completely nor touching the window.
    Let me know your thought or advice.

    • Hi Jay,
      If you have condensation forming inside your RV you have too much humidity inside. So, you either need to vent the air better to get rid of moisture from showering and cooking and from you just breathing or you need a good dehumidifier. That should do the trick.
      Please let me know what you decide to do and how it works for you.
      Thanks for reading the article!
      Safe travels,

    • I’ve just been researching this topic as I’ve moved my fifth wheel to a much colder climate and need to prepare for winterizing in a few months. Condensation is one of my concerns for this upcoming winter. I’ve read people have had better luck keeping condensation down when the reflective barrier is on the outside of the window as well as the inside.

    • Try leaving the bathroom vent open. It allows any buildup of humidity to escape while not creating an excessive loss of heat or cooling. Once I started doing this, I haven’t had any more problems with humidity build up and mildew on my windows.


Leave a Comment