Tutorial: Steps to install your own projecting windows on your camper vans

 

We are addressing a crucial topic: the installation of sliding windows and projection bays on your converted van or motorhome!

In this article, we will show you how to install sliding fixed windows!

Although we are installing the windows on a Sprinter, the steps and preparation can be applied to almost any van and window bays of the same type, including Ducato, Crafter, Renault Master, Combi T5 converted vans, etc.

We opted for windows designed for a motorhome with a wall thickness of 35mm because they are a bit cheaper than windows specifically designed for a Sprinter, but they did not require more work on our part to be installed correctly. In the end, we come out ahead, as given the cost, it was really worth it.

Below you will find links to the bays.

Installation supplies for projection bay on converted van

Below you will find links to the items we used for this project.

Projection bay 30×90 (identical to the fixed one we used): Link

Sealant: Sikaflex 710 TX

Step 1: Cut the internal reinforcement

 

When installing your bay, you need to ensure that there is enough distance from another source of airflow in order to maximize airflow throughout the van.

In our case, a roof fan was installed just behind the driver's area, so we positioned the bay to be installed at the back of the van.

Before we could cut the window hole, we had to remove the vertical reinforcement inside the van. We carefully used an angle grinder to cut the reinforcement while trying not to hit the van's sheet metal.

Step 2: Polish the cut edges

 

Once we cut the reinforcement, it was held on the van wall by a foam adhesive, and we simply used a pair of pliers to remove the reinforcement.

Next, we used our angle grinder to round and polish the sharp edges and scraped off the adhesive with a flathead screwdriver. Even though a scraper would have been smarter to use.

Step 3: Prepare the walls before cutting the bodywork

 

We traced the perimeter of the window on a piece of cardboard and cut it out to make a template. We glued the template to the van wall and traced the perimeter with a marker. We positioned it by eye and then measured to the nearest reference point, so we could copy the position on the other side.

After removing the template, we drilled holes near each corner to insert the jigsaw blade. To minimize scratches on the van's paint, we applied tape to the bottom of the jigsaw. You can also apply tape to the part to be cut on the bodywork to reduce debris.

Step 4: Cut the window hole with a jigsaw

 

Using a metal cutting jigsaw blade, we started from one of the holes we drilled and cut around the marked line.

The first two sides are easy to cut, but once you reach the third side, the structural integrity of the cut sheet is almost nonexistent, making it very wobbly during cutting.

We tried to stabilize it with tape by sticking the cut sheet to the rest of the bodywork, but that wasn't very helpful, so one of us held the cut to keep it steady, and that worked relatively well.

Once we cut the window opening, we smoothed the edges and spray-painted anti-rust paint along the edges to protect the bare metal.

Step 5: Measure and install the appropriate wooden reinforcements for your window

 

As we mentioned earlier, the windows we purchased are designed for motorhomes with a wall thickness of 35mm. To fill the difference, we traced the perimeter of the template we made earlier on a 10mm plywood sheet, then used a 2.5cm space to trace a wider frame border around that same template.

We cut out the inside and ended up with a rectangular frame that we will use to place between the window and the window counter-frame.

Step 6: Cut the wooden support frame with a hole saw and a jigsaw

 

We cut out the inside and ended up with a sort of donut/rectangular frame that we can use to place between the window and the counter-frame (inner frame) of the projection bay.

Step 7: Optionally add butyl tape to the window trim

 

An alternative to sealant is to apply Butyl Tape. The same step can be performed with a sealant type Sikaflex 710 TX.

Now that we have made the hole for the window cutout and the spacer. All that remains is to apply the sealant to the window so that it remains watertight.

We press the butyl tape around the edge of the window. One thing we did not take into account is that the flange has a slightly rolled edge, so we should have doubled the butyl tape to ensure that there is enough sealant between the window and the van's bodywork.

Step 8: Clean the contact surface and install the window

 

Fortunately, we cut the hole large enough for the window to fit without any additional cutting.

After the dry fit, we cleaned the contact surface to ensure there were no debris that could hinder the sealing.

Next, we install the window from the outside. One of us stepped back a few meters to confirm that the installation is parallel to the ground.

Step 9: Assemble the inner frame

 

With one of us holding the window from the outside, we install the wooden donut frame and then the counter-frame of the projection bay.

We retrieved #8 self-tapping screws to secure the window in place.

Step 10: Gently screw the counter-frame onto the wooden frame and the bay

 

We recommend using a bit of lubricant on the self-tapping screws before driving them in as some may break. This will save you from having to drill new holes in the counter-frame. After learning our lesson on the first window, the installation of the second window went much more smoothly.

We suggest starting by hand-screwing, then lightly using your drill until the screws are properly inserted.

Step 11: Sealing test (IMPORTANT!!)

 

To ensure that everything was installed correctly, we tested it with water from the hose.... And surprise... we found a lot of leaks.

Step 12: Attention: Make sure to remove the drain plugs before testing the seal

 

After further inspection, we realized that part of the water infiltration was due to tiny gaps in the butyl tape. So we filled the perimeter with silicone sealant type Sika Flex.

But most importantly, we forgot to remove those drain plugs, which are meant to drain water that gets into the bay frame. So... remove the drain plugs before testing the watertightness of your bay.

Step 13: New sealing test

 

After correcting these small mistakes, we sealed the windows! It will be great to have these windows to look out of when we hang out inside the van and to have the option to open them for a little breeze inside.

Step 14: Admire your work

 

Note that this installation method applies to all types of bays (projection, sliding) with an aluminum frame. You can find here our bays in stock and here all our sealants and promotional items.