One of the first projects that we completed in the van was installing a fan for adequate ventilation. What better way to kick off a relationship with your newly acquired vehicle than to cut a big hole in its roof? The installation was a bit unnerving at first, but as soon as we knew we had the right size cutout it was a breeze. Here is how we approached it:
- Maxxair 6200K Fan
- Dicor Butyl Seal Tape
- Dicor 501LSG Lap Sealant
- 3/4″ Plywood or piece of wood
- 1″ aluminum bar
- Nuts, bolts & washers
- POR 15 Rust proof paint
The Maxxair 6200k was picked over a similar model Fantastic Vent fan because it is designed with the option to be open during driving and when it rains, and the latter was definitely a key point for us. After doing research on sprinter-source.com and various blogs, we knew we wanted to install the fan using a sandwich method. What it entails is having a solid base to screw the fan into, instead of only the roof’s sheet metal. The sandwich that you end up creating consists of lap sealant, aluminum bars, fan flange, butyl tape, van roof, and 3/4″ plywood in order from top to bottom. All of that is held together using bolts and securing with nuts from the bottom.
If you are installing a Maxxair 6200k fan on your vehicle, the first step you’ll want to complete is cut out your wood (3/4″ is a solid base to use) to a 16.5″ by 16.5″ square. Then you’ll want to cut the dimension of the fan flange to fit into that piece of plywood, which is 14″ by 14″. Once you jigsaw that piece from the 16.5″ plywood piece, not only will you have the bottom most layer of your sandwich, but also a square template to make sure that the vent cutout is centered and avoids the ribs on Sprinter roofs. As our Sprinter is a 2007, we were lucky enough not to have a circular rib in the back of the van as most of the newer model years do, and had the option of installing our fan on the anywhere that best fit our layout. Due to our planned roof setup of solar panels and Thule carrier box, we decided to install the vent in the back of the van towards the driver side.
Using the previously cut out 14″ template, we used Gorilla tape to temporarily mount it to the roof once we had our ideal location determined. We drilled a center hole into the roof using a 1/8″ drill bit and mounted the template with a nut and bolt to align it properly and to outline the edges of it with a sharpie. With the template unmounted, we drilled each corner of the marked square using a 3/4 Countersink drill bit. Some folks opt to leave the template in to have a good base to cut around, but we had a few jigsaw blades designed for cutting metal and weren’t concerned about it slipping away. We cut the square hole following the black sharpie lines from corner to corner, and soon enough had a 14″ hole in the roof of our van.
The jigsaw blade for metal worked well, but we had to file some of the jagged edges. Once that was done, we mounted the fan flange into the hole to determine where to drill holes in the roof for securing the entire sandwich. We drilled holes in the roof as well as the plywood template, and then used some of the leftover POR-15 rust proofing paint on the hole edges to prevent it from rusting. Once that coat tried, original paint was applied over it. It took another 30 minutes to dry and by that time we were ready to apply butyl tape on top of the roof. The Dicor tape is just about the right width for the fan flange and after putting two layers of it on top of the roof, we pressed the fan flange against it. While the paint was drying the aluminum bars were also cut to size and pre-drilled, so they were ready to be mounted above the fan flange.
Once the plywood, flange and aluminum bars were all secured with bolts, the next step was to apply lap sealant over the flange to prevent leaks. The stuff is very messy, so we took our time here. It takes a bit to dry, but does spread evenly. Once the lap sealant dried, we were done!