RV 101® / RV Education 101®

There are different types and styles of RV windows, but one of the most popular is a clamp ring style window. When you install the window there is a clamp ring on the inside with holes around the perimeter so you can screw the clamp ring into the window’s frame. As you tighten the screws it clamps and seals the window in place. This is the style of window we are discussing today.

We purchased an older 5th wheel project trailer to produce some RV do-it-yourself and RV how-to videos on. The videos are basic upgrades and repairs RV owners can make on their RVs. The videos will be available on our RV Education 101 and RV 101 YouTube channels.

You might need to replace a broken window, reseal a window or remove a window to repair water damage, which happens to be the case with our 5th wheel project trailer. During my inspections of the trailer I noticed signs of water damage on the rear wall. After removing the interior paneling I saw a small amount of water damage around the window, and needed to remove the window to make repairs.

On the interior window frame you will notice numerous screws. These screws secure the clamp ring to the frame and seal the window. Using the correct screwdriver tip remove all of the screws. Keep in mind when the screws are removed the window is ready to come out, so it’s a good idea to have somebody outside too. If the sealant around the window is still good it might take a little effort to get the window out, but it will come. You might also notice some small spacers around the window frame. Make a mental note where the spacers are located for installation.

With the window and interior paneling removed I could assess the damage. In lots of cases it’s necessary to remove the corrugated aluminum sheeting from the exterior too, but the damage was minimal and I was able to make repairs to the window frame and wall from the interior. After the framing repairs were completed and new insulation was installed I cut and stapled new interior paneling to fit around the window opening. Now it’s time to re-install the window.

The first step is to clean the old sealant from the exterior metal or fiberglass and from the window frame itself. I use plastic scraping tools that are designed to remove automotive trim for this job. They come in several different sizes and shapes, and they work well removing old dried putty and butyl tape. The cleaner you get all of the surfaces the better the window will seal.

After all of the old sealant is removed you can use a cleaner that is compatible with the exterior of the RV, and as a final prep I like to go over the surface with some denatured alcohol on a rag. The exterior metal is usually stapled around the window opening. On this trailer some of the old staples were rusted so I removed them and re-stapled the metal.

After the exterior surface and window frame are clean it’s time to install new butyl tape around the window frame. I prefer butyl tape over putty tape because it does not dry out like putty tape. You can purchase butyl tape at your local RV dealer. When you install butyl tape on the window frame make sure all the screw holes are covered and put the butyl tape around the entire perimeter of the window frame, leaving no gaps. If your RV has the uneven corrugated aluminum sheeting on the exterior its a good idea to add more butyl tape to the low areas in the metal so the window will seal properly.

When you reinstall the window have one person inside and another person outside. Make sure the window is installed right side up. There are weep holes in the window frame that allow water to drain out of the track. The weep holes go on the bottom. After you get the window in the opening make sure it is spaced evenly around the perimeter. This is where remembering the placement of any spacers is helpful. While the person outside holds the window in place the person inside can install the clamp ring and start a couple screws.

The holes in the clamp ring will line up with the holes in the window frame when it is installed properly. If you need to replace the screws for any reason make sure they are the same size and length as the old screws to prevent damaging the window frame or glass. Start the screws and slowly work around the entire frame snugging the screws. Do not tighten screws on one side before the screws are installed on the opposite side. Snug all the screws and then go back around tightening them again. The person on the outside should start to see the butyl tape ooze out around the window frame as the screws are tightened. Do not over tighten the screws.

After the window is installed use your scraping tool to remove excess butyl tape from around the window frame. The final steps is to run a bead of caulk on the top of the window frame and slightly around the corners. This will allow water to run off and help prevent future water damage. Make sure the caulking is compatible with the surfaces you are sealing.

If you are careful and take your time it is not difficult to replace or reseal a window in your RV. If you are not comfortable working on your RV have it done by a qualified RV service facility.

For more information on maintaining your RV, check out our RV Care & Maintenance Video Course

Happy Camping,

Mark J. Polk

RV Online Training