RV Window Replacement – How to Measure, Replace and Install an RV Window

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As they make up parts of the exterior of a camper, RV windows not only come into contact with elements regularly but also sustain occasional impacts. While RV windows don’t break easily, it’s wise to have a general idea about RV window replacement in case a need comes up. 

All in all, replacing windows for RV is not a difficult task to pull off but it’s far from a walk in the park. It only takes one mistake for your project to run into various issues from ill-fitted frames to loose glass. That is why you must spend a bit of time researching the process in advance. If you manage to get a firm grasp of the steps involved, the odds of successful replacement would increase significantly. 

Preparation: Tools And Gears 

You don’t need fancy stuff to replace an RV window but for good measure, make sure that you have the following before starting the project.

  • Power drill (ideally a cordless): Motorhome window replacement often necessitates the drilling of a few holes here and there. That means it’s a good idea to get your hands on a power drill. Nowadays, you could choose from all sorts of models but you should stick to cordless ones for ease of movement. Feel free to use a corded drill in a pinch. 
  • Tape measure and ruler: To optimize the fitness of the frame and glass during window installation, you have to collect measurements of the window opening. As a result, it’s essential to keep the tape measure and ruler by your side. You may use whatever tape measure you have but remember to use a ruler with measurements that run all the way to the end. 
  • Painter’s tape: In RV window installation, you need to apply various substances so it’s wise to stock up painter’s tape. By taking advantage of painter’s tape, you would have an easy time preventing messes as you install new windows. 
  • A pair of scissors: The replacement of windows on campers involves a lot of cutting which is why you should pick up at least one pair of scissors. With scissors, you could cut through things such as painter’s tape, insulation materials and so on. 
  • Putty knife: Featuring a thin blade, putty knife excels at getting in tight spots so it’s the best tool for breaking seals, removing sealants, cleaning debris, … Considering the work involved in window installation, a putty knife is by all accounts a must-have. 
  • Sealant and caulk gun: For your information, the sealing of windows affects the insulation of the interior of RV. Thus, to avoid losing heat in the winter and cool air from A/C in the winter, you have to pay special attention to sealing. To seal windows, all you need is a caulk gun with sealant. 
  • Rubbing alcohol and mineral spirits: Once it comes to cleaning up particles and excess sealant, a combination of rubbing alcohol and mineral spirits works wonders. Handle these solutions with care though because you don’t want them to spill all over the place.
  • Rags: No matter how careful you are, there is a very good chance that you would make mistakes on occasions. Therefore, it’s strongly recommended that you prepare rags to wipe clean the messes. In a hurry to replace the windows? Then you could tear old T-shirts into pieces of cloth.
  • Ladder: You always have the option of parking your rig near high grounds to access the top section of windows. However, you should think about grabbing a ladder for maximum stability while installing RV windows

About personnel protection equipment, you need to gather gloves, goggles, respirators and so on, depending on what you work with. Some of the stuff above may cause serious injuries and health issues if you fail to exercise caution.

How To Measure RV Windows 

In the beginning, it’s widely advised that you move the shades, blinds and curtains of windows out of the way. Next, unscrew the screws before detaching the frame of the windows from the window openings. It’s worth pointing out that sometimes, not many things hold the outer part of RV windows in place. Because of that, you must refrain from exerting too much pressure on the windows to stop them from falling out. 

Measuring Window Opening

  • For standard rectangular windows, you usually need to measure the width and height of the window openings. Still, to be thorough, it’s best to take measurements at several points to determine how smooth the openings were cut. In the case that the measurements match, you could move to the next step. On the other hand, if inconsistencies exist between measurements, note them down as references for window manufacturers.
  •  For windows with odd shapes, you should first consult with the manufacturers to get the exact measurements. Afterward, measure the window openings again by yourself as a precaution. 

Measuring Sidewall Thickness 

In general, sidewall thickness indicates the depth of windows stretching from the exterior wall to the interior wall. To measure sidewall thickness for RV window replacement, get a hold of your ruler and insert it into the wall. When the ruler stops going in, check out the measurements on it to deduce the sidewall thickness. Repeat the process several times for optimal accuracy. 

Measuring Window Corner Radius

Most modern windows for travel trailers on the market have round corners with radius varying between 2.5 inches and 3 inches. Nonetheless, to reduce the risk of problems with fitness in the future, you need to measure the window corner radius precisely. One easy way to measure window corner radius is to use a Radius Measurement Template. You should be able to print one if you have a printer on your rig. Use the scissors to cut around the printed template, press it against the corner and read the measurement. 

Keep in mind that the template only works if you print it properly so you may want to take a look at printer settings beforehand. Normally, since templates for radius measurement have measurement limits, you could decide whether you have a good printed template by measuring it with a ruler. 

How To Replace RV Window

Assuming that you nail the measuring for your windows, proceed to order window replacements with the numbers you have. Once you receive the windows, go through the steps down below to install them. 

Step 1: Remove The Old Window

Like collecting the measurement, you need to remove the frame of the window while keeping the outer part from dropping outward. If you come across sealant, use the putty knife to get rid of it but be gentle so you don’t leave scratches. Next, exit to the outside and use the putty knife to break through the seal of the window. To stay on the safe side, open your window, grab it with one hand and use the other hand to work on the seal. 

Use rubbing alcohol and mineral spirits to process the area around the window opening. The last thing you need is for debris, sealant and so on to stick around the opening during RV window replacement so be thorough here. 

Step 2: Dry Fit The New Window 

On the new window, you must remove the adhesive strips that hold the ends of the frame together then set the frame aside. Afterward, get a hold of the new window, move outside and place it into the vacant window opening for dry fitting. Use the opportunity to check the alignment of the new window to ensure that there is nothing out of the ordinary. Don’t worry if you notice gaps at the top of the new windows because you could address those using a couple of shims. 

Step 3: Install The New Window 

Wipe the new window with rags soaked in rubbing alcohol to free its surface of particles. In the next step, apply a strip of double-sided, closed-cell foam tape around the center of the bottom of the new window. For a good measure, you have to consider overlapping the strip of tap by at least ½ inch. It’s suggested that you remove the paper backing of the tape prior to rounding corners to achieve an unbroken seal.

Now, you should sprinkle some water on the tape as well as the window opening. Though spraying water sounds counterintuitive, it actually allows you to set up the new window and keep it from sticking to the sidewall. The moment the water evaporates, move the new window into the opening, orient it a bit for optimal fitness and press it against the frame. After that, assemble the inside frame and install the screws to secure it. In the case that you don’t mess up anywhere along the way, the RV window replacement process is nearing its end. You just have to install the drain covers to the bottom, get the screen into its track and apply sealant to the window. Your new window is ready-to-use after you manage to wrap up everything. Open and close the new window a number of times to see it’s working as expected.

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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