how to install side panel bunk windows on a spritner van
Sprinter Van Build Series

How to Install Side Panel Bunk Windows on a Mercedes Sprinter Van

Taylor and I recently bought a 2015 Mercedes 170” Cargo Sprinter Van, with plans to convert it into a home on wheels. Our goal is to take this van all over North America eventually reaching Alaska.

To help inspire others, we are documenting our journey and each step of our van build, creating video tutorials on youtube along the way.

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Since we have a cargo van we did not have any windows in the van other than the driver’s side, passenger side, and windshield (obviously) so we needed to cut out the metal skin of the van to install our windows.

We originally thought we were going to get them professionally done but then we decided to save money and do it ourselves. Below is a step by step tutorial on how to install side panel bunk windows on a Mercedes Sprinter van. We recently wrote a post on how to install back door windows on a Mercedes Sprinter van as well.

If you’re interested, consider subscribing to our Youtube Channel for more van build episodes and tutorials!

Tools Needed To Install Side Panel Bunk Windows

We purchased the side panel bunk windows from CRL through Amazon and really like them. The windows come with a screen over the sliding hatch to allow ventilation into the bedroom area without worrying about anything flying into your van. This is critical for nights when it’s really hot outside and we need good airflow.

Before we get into each step of the side panel bunk window installation, below are tools used.

Step by Step Guide

If you enjoy watching videos rather than reading, check out our video tutorial showcasing step by step on how to install a side panel bunk windows to your van.

1. Create a Template for the Window

The first thing you need to do is take your CRL side panel bunk window out of its box and create a template, I did this using cardboard.

Create cardboard template how to install side panel bunk windows on sprinter van
Using cardboard to create the window template

Note you want to trace the inside of the window (the smaller side), NOT the outside of the window. Since the handle gets in your way I cut a small square in the middle of the cardboard template so I could get it flush against the window.

You will use this template to determine the positioning of the window against the wall of your van as well as tracing the template to the van when it’s time to cut the hole for it.

2. Determine the location of the window in your van

Take the cardboard template that you just created and line it up with the inside of your van to determine exactly where you want it. We installed ours in the back window frame closer to the top of the frame due to our elevated bed/bench.

Determine template location on window
Aligning the template using tape to hold it in place.

If you do not have an elevated platform then you may want to lower your window location.

3. Cut out the window ribs of the van’s frame

Once you have your outline traced in the inside of the van, you will have to cut out the ribs of the window frame. One thing to consider, since you will use the backing plate to secure the window in place (which extends beyond the cardboard template) you will have to cut the ribs about an inch further than your template.

This picture illustrates what I am referring to here.

Removing the ribs of the van - how to install a side panel bunk window
You can see the marker lines on the ribs, notice I cut above those lines

This is critical that you do not cut into the wall of your van. If you do it will cause damage to your van and will need to get repaired in order to finish the project. I used a grinder to cut through the ribs and took my time!

cutting the ribs of the van in window frame
Using a grinder to cut out the ribs of the window frame.

4. Trace Your Template and drill 2 holes

Once you have the ribs cut out trace your template precisely to your van, ensuring it’s exactly where you want it. Then drill two holes through the van. This will help you determine exactly where to make your cut from the outside of your van.

drilling pilot holes into your van - sprinter van in stall bunk panel windows

5. Trace template outside the Van

With the pilot holes, you just drilled through, leave the drill bits in the hole and bring your template outside the van and secure it in place. Note you want to make sure to mark which side of the template is facing the front of the vehicle and which side is towards the back. This will help ensure it stays exactly where you want it.

trace template on outside of van for installing a bunk panel window

6. Cut the trace template from outside

Once you have the hole traced it’s time to prep for the cut. Use masking tape to protect the metal around the window trace to prevent scratching when using power tools. I should have done that before drilling the pilot hole and recommend you do the same!

drill hole into the wall of van - how to install side panel bunk window
Drilling the pilot hole to fit the jigsaw blade.

Following the traced outline of the window use a jigsaw to cut through the van wall for your window. Remember to tape the outside of the trace to ensure you do not scratch your vehicle and remove the paint. Also in order to get the jigsaw started, I usually drill a large hole into the van first.

cutting the side of the van - how to install side panel bunk windows on sprinter van

7. Grind the rough edge of the metal

Once you make your cut you will want to buff out any rough edges from the jigsaw. I used a metal filer to do this but you can use other grinders as well, just make sure you do not grinder down the shape of the window.

buff out rough edges of van - how to install side panel bunk window

8. Paint the raw metal

After buffing down the raw metal edges, paint the raw metal with an oil-based paint like Rust-oleum. This will prevent rust and increase the longevity of your van.

Paint the raw metal with rust-oleum paint

9. Insert Window (Butyl Tape)

After painting the window cut out it’s ready to install the window.

If you want, you can use Butyl Tape with the CRL window, which we did. If you do I recommend only using one strip of butyl tape and use black color tape.

Adding butyl tape to the window - how to install a side panel bunk window

Don’t forget to clean the van wall before inserting your window into the cutout hole. You want the van frame as clean as possible to ensure you get the best water seal.

insert window into the wall how to install a bunk panel window

10. Screw in the backing plate and secure the window

Once you have your window in place and lined up, push the window and the butyl tape to the metal of your vehicle. Then from the inside of your van screw the window into place with the backing plate. You may need to have someone push on the window from the outside while you screw it into place to get the screws as tight as possible.

screwing in the backing plate to the window - how to install side panel bunk window

11. Test the window for leaks!

The window is installed and ready to go, it’s time to test the window with a water test. We grabbed the hose and sprayed the side of the van down with water to see if any water seeped through. If your window is screwed in tightly you should be good to go and you’re done.

All done ready to go - install side panel bunk window on van

Make sure to clean up and remove any raw metal shavings from cutting out the window!

Summary – How to Install Side Panel Bunk Windows

Overall this project is doable but takes precision because you can cause serious damage to your vehicle. The most important thing to watch out for is cutting off the ribs of the window. You need to ensure you do not cut through the wall of the van when removing the ribs. If you do that you should be good to go!

If you’re interested in other van build posts, check out the following:

Before we decided to buy our own van we rented one to test the waters! This helped us realize it’s something we really want to do since buying a van and converting it is a lot of money and a lot of effort! We rented a van in Portugal and absolutely fell in love with van life!

A heads up: This blog post is a review of the van we rented, not really a van life video.

If you have any questions about how to install side panel bunk windows to your van, drop a comment below! If you’re interested, please follow our van build series where we will document every step of the build process as well as our youtube channel!

As always, thank you for reading/watching our content!

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