How to Install a Maxxfan Roof Vent on a DIY Van Conversion

Maxxair Fan Installation

How to Install a Maxxfan Roof Vent on a DIY Van Conversion

Installing a Maxxair Maxxfan Deluxe roof vent on a DIY camper van conversion helps controlling temperature inside the van, relative humidity (condensation and moisture), indoor air quality and creates air movement. Don’t be intimidated by this task, it is well within the average DIYer’s reach! Let’s do it!







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  • Jigsaw & metal blades (have some spare blades, we broke one in the process)
  • Files
  • Sandpaper
  • Caulking gun
  • Vacuum (metal chips will be all over the place. Get rid of them as soon as possible to avoid scratches)
  • Screwdriver
  • Safety Glasses and hat
  • 4 x C-clamps


Maxxfan Installation, Material
Material for Maxxfan installation


How we installed the Maxxfan roof fan on our van


1- Install painter’s tape and mark the fan cutout

To mark the fan cutout, we used the interior side of Hein’s Ford Transit RV roof vent adapter and it was super easy since the adapter will “locate itself” in the center of the sheet metal panel. Sweet!

Drilling and cutting practice


2- Practice makes perfect…

We “simulated” 2 holes and a straight line to practice drilling & cutting on the panel we were getting rid of. It’s a good thing we did it! We learned that it’s better to make the corner holes a bit outside of the cutting line (the fan flange allow some over cut) AND that a storm of hot-burning metal chips will blow on your face and into your hair. WEAR PROTECTIVE GLASSES AND A SEXY BANDANA ON YOUR HEAD. You’ve been warned.

Practice makes perfect for maxxair fan installation


3- Get ready to cut the crap out of your brand new van. And enjoy!

Cut the crap out of your brand new van


4- Drill 4 holes at each corner, large enough to let the jigsaw blade through

Maxxair Fan Installation,, Drill 4 holes


5- Cut each side, then apply duct tape to retain the panel from falling at the last cut

Maxxair Fan Installation, cut each side


6- Break the sharp edges with a file and smooth the edges with a fine sandpaper

Maxxair Fan Installation, Break Sharp Edge


7- Install Hein’s adapters (interior and exterior) and the fan flange and drill all holes

We used 4 c-clamps to ensure nothing moves during the process.

Maxxair Fan Installation drill holes

TIP: Slightly oversize all holes on the interior adapter for easier re-assembly. Do it.


8- Break the holes sharp edges and smooth with a sanding paper


9- Clean the surfaces to be touched-up with isopropyl alcohol


10- Apply Primer, Paint & Clearcoat on fan cutout and drilled holes

This is an important step to avoid corrosion in the future.

TIP: You can have your exact van color prepared for you in almost any auto-parts store. Just give them your color-code (printed on the driver’s door frame), year of production and make.

Maxxair Fan Installation,, primer

Maxxair Fan Installation, paint


11- Clean fan flange with isopropyl alcohol


12- Clean van sheet metal with isopropyl alcohol


13- Apply butyl tape on the fan flange (on the surface that will be mating with the fan adapter)


14- Apply GE Sillicone II on Hein’s fan adapters surfaces that will be mating with the van

This is to prevent moisture retention and corrosion.


15- Assemble Hein’s adapters and fan flange all together with the fastening hardware

We used washers both on the interior and on the exterior surfaces.

We did not oversize the holes on the interior fan adapter. With the butyl tape and sealant, it was difficult to re-assemble…

Maxxair Fan Installation, install screws


16- Apply Dicor self-leveling sealant around the periphery of the flange

We ensured to cover the van panel, the fan adapter and the fan flange. We also covered all the screws.

Maxxair Fan Installation, apply sealant


17- Install the Maxxfan unit through the fan flange and fasten using the 4 provided screws

Maxxair Fan Installation, Install Fan Unit


18- Look at our fan

Just look at it.

Maxxair Fan Installation, final
We have a Maxxfan!


19- Final Test

We tested our Maxxfan using the wires from an adjacent light that we removed.

(note: we blew a fuse doing the same thing afterward: no surprise, the interior lightning fuse of 7.5 amp located at position F32 is not designed to withstand the load of an additional fan… no big deal, the fuse was replaced and the light is back!)

It works!

Maxxair Fan Installation, testing the fan


20- Have a pint of fresh Session I.P.A.

We deserved it!

Maxxair Fan Installation, reward




On Second Thought…

We’ve been using the Maxxfan since June 2016, here’s our review:

Maxxair Maxxfan Deluxe Roof Fan Review






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Hello! We’re Isabelle and Antoine 🙂 In 2017 we sold our house (and everything in it), quit our engineering careers and moved into our self built campervan. We’ve been on the road since then and every day is an opportunity for a new adventure; we’re chasing our dreams and hopefully it inspires others to do the same!




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55 thoughts on “How to Install a Maxxfan Roof Vent on a DIY Van Conversion”

  1. Hello,

    I ordered the Heins adapter because of your recommendation. I have just watched several videos on Maxx Fan installations. I have not seen one with Heins adapters in them. Are these really necessary. I have a 2019 Sprinter and the surface where I plan to install the fan, (rear of the van) seams pretty flat. Do I need the adapters??

    Also I wonder why you don’t have the step of adding the interior trip ring after you complete your ceiling? All good information. I have started the build!!!!!

    David Jackson

    • The interior surface is pretty flat, but there are corrugations on the exterior. So outside adapter is GREAT, inside adapter is not needed (I don’t know if they sell the interior adapter anymore anyways). If where you plan to install the fan is flat, then you don’t need the adapter 🙂

      Sorry what’s the interior trip ring? Do you mean the “decorative” trim? It was added later so there’s no pic in this article, but you should see it in our van tour:

      Good luck!

  2. Hey all! We are about to start this project in our Transit Mid Roof… cutting a huge hole in a new van seems so WRONG! I wanted to ask you about your primer, paint, and sealant. Did you use epoxy or urethane primer? Did you use spray sealants? Excited to get our build started, thanks for the inspiration!

    • I honestly can’t recall… We went to an Auto Parts and gave them our color code. Don’t buy the all-in-one (primer + topcoat) stuff. We recommend to get the spray cans, but don’t spray directly to the surface. Spray in a plastic jar to get a little paint, then use something to apply it to the surface.

      Good luck!

  3. You mention “adapters” as in plural. However when I ordered the adapter from the above link, I received just one, which appears to be the one to mount on the outside of the van. There is no inside adapter. Has something changed?

  4. Hi! We actually have a Ford e350, but we’ve adapted most of your instructions to work with our van! It’s been great. We’re about to install our Maxxair fan, but we’ve noticed that some other websites/blogs don’t use an adapter at all…but maybe they are making a huge mistake? Have you heard of anyone installing a Maxxair fan without an adapter and it being successful?

    • An adapter is not mandatory, you could probably use layers of sealant instead (butyl tape?) to create a flat surface. But the adapter makes the job MUCH easier and ensure a proper seal (since it fits perfectly with the roof’s corrugations).

      We highly recommend it, but it’s you call in the end 🙂

  5. On the maxxair fan instructions it specifically says not to use Acetone on the plastic. Step 11 in your guide says to clean the fan flange with Acetone.


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