Floor Vent


Floor Vent

Adequate ventilation is crucial to control temperature, humidity level and to evacuate smells from cooking; that’s why we installed a Roof Fan (faroutride.com/fan-installation/). The job of the roof fan is to take air from inside the van and pull it outside the van. The evacuated air needs to be replaced with fresh air or the roof fan won’t be able to do it’s job! If the fan is located in the rear of the van, the front windows could be used as air intake. If, like us, the roof fan is install in the front of the van, there should be some intake somewhere in towards the rear of the van. Here is our approach on that matter:

1- Add an air intake under the fridge, so the fresh air helps reduce the workload of the fridge (and save on electricity). This is covered in this article:



2- Add an air intake at the back of the van to cool down our bedroom. This is covered in this article, keep reading!!



We installed a duct from the floor vent to above the bed, because we realized that fresh air would not come up above the bed; it was really hot up there! The duct is attached with velcro straps so it can be easily detached, extended and located almost anywhere on the bed; it’s a cool feature when we’re reading or just chilling on the bed!

Floor Vent, Duct (3)
The black thing on the left is a 3-axis mounted fan, we highly recommend it! Buy on Amazon.



Before you go ahead with the floor vent, please read our “On Second Thought” at the end of this page!





TOTAL COST : 80$ USD without fan, 130$USD with fan.


DISCLOSURE: This post contains affiliate links, which means that if you click a product link and buy anything from the merchant (Amazon, eBay, etc), we will receive a commission fee. The price you pay remains the same, affiliate link or not.







*Disclosure on the fan: This is a bilge air blower fan. It’s designed to push A LOT OF AIR for engine compartment of boats. It’s VERY NOISY and draw a lot of current (6.5A at max speed, but it’s similar to a computer fan at low speed ). If you choose to install it, be aware that it’s too loud to be run at night and make sure to install a Speed Controller because it will only run at full-speed (like, crazy-supra fast). We think it’s not mandatory to install the fan, but it’s kind of nice to have when it’s really hot.







Let’s first make a hole in the floor. We don’t mind making hole in the van anymore, we’re getting used to it! 🙂

HINT: Start with a small pilot hole (like 1/8″ or such), so if you’re slightly offset (go look under the van to confirm the hole location) you can start over; the 4″ hole will “swallow” your first miss located pilot hole…


Drilling into the van metal floor exposed edges to corrosion, so as usual we sanded the bare edges and applied primer + paint + clearcoat. We sourced them from our local Auto Parts Store (It’s better to use a can. Spray it into a jar and use a Q-Tip to paint the edges).

Floor Vent, Paint


The Valterra Slip Hub (3″) will be installed under the van. But first, let’s get rid of the small flange; it’s useless to us (and will prevent us from installing a mosquito screen):

Floor Vent, Cut Flush


There is also an “inside flange” (for a lack of better term) that we can trim away; trimming it will increase inner diameter = more air flow!



The Valterra Slip Hub is installed under the van. Notice the small, white, no-see-um mosquito net sandwiched between the wire mesh and the slip hub! (we will install a dust filter a bit later)
Floor Vent, Valterra Installation


This is looking from inside:

Floor Vent looking from inside


We want the floor-vent to be easy to close/open, so we’re adding a Blast Gate Valve.

It will be stuck to the floor with 3M VHB Tape (and act as a sealant against water spill). The Blast Gate’s flange that is inserted inside the floor hole is a bit too long, so we trimmed it away:



Then the Blast Gate is just pressed against the floor to secure it in place:

(the following pictures were taken once the van was completed…):

Context: The grey thing on the right of the gate is a torque wrench; the wood platform above is to support a toolbox. On the very right is the slide-out-bike-tray.



A duct will run from the floor hole to above our bed, so we drilled a 4″ hole in the platform bed and inserted a 4″ splice:

Floor Vent, Splice 1

Floor Vent, Splice 2


We then attached (with Powertec hose clamps) the in-line fan and the duct from the floor vent to the bed platform (if you chose not to install a fan, well, don’t install a fan just route the duct):

Floor Vent, Duct (9)

The duct is held on the wall with plastic coated hanger straps.


Then we attached the top duct with D-Ring picture hangers (Buy on Amazon) and velcro straps (Buy on Amazon). We located the fan speed controller so we can access it from the bed or from the back of the van:




We added a dust filter, because we learned the hard way that dust will get sucked in on dusty roads… The filter just holds with the mesh screen sharp ends:

Floor Vent, Dust Filter
This picture sucks and the filter should be cleaned… we’ll clean it we promise!



That’s it!

Stay Cool!





September 2018 Update

So we just went through a summer and it was a HOT one! Here are our thoughts:

PROS: The floor vent is great for when we leave the van alone (in the city or when riding or bikes); indeed it’s super safe, there’s no potential for thief through that, nice. If we had a window instead of the floor vent, we’re not sure if we could leave it opened in urban areas…

CONS: It’s not much effective as passive vent because the hole doesn’t have enough surface area. When it’s super hot outside, we wish was had a slider window in the back to get more ventilation without having to start the inline fan (as we mention the inline fan is a little noisy). We consider adding a window in the back for next summer.

DUST: The floor vent located at the back of the van collects a lot of dust! We need to clean our dust filter quite often. However the fridge floor vent is not that bad since it’s located near the front.






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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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24 thoughts on “Floor Vent”

  1. Sir, you mentioned to add a slider window at the back, I was wondering, would another maxxfan at the back be better? I am considering this design, please share with me your thoughts.

    Thanks loads!

  2. I stayed pretty comfortable sleeping in the summer with a rear-mounted ceiling fan/vent (blowing downwards), with the front windows cracked two inches. Difficult to keep van cool and secure in urban areas while you’re gone during the day. Doing it again, I’d do two rear side-mounted windows with a mid-mounted ceiling fan/vent (like yours). And maybe a larger (non-powered) floor vent towards the front, like 8 inches wide.

    Fun side point – I ran the Fantastic fan all the time during light rain and moderate speeds (up to around 45mph). It was fine!

  3. As always thanks for the great post. I had two questions about this:

    1) Do you use this in the winter or do find it too cold?

    2) Did you consider installing 2 inline fans in opposite directions to be able to reverse airflow?

    My thought is that I need two air flow vents for proper ventilation but in the winter will not want cold air on my face thus if I can reverse it, it will pull the warm moist air out and I’ll leave the roof fan cracked as a passive air vent. THoughts?

    – Andrey

  4. Question regarding hole placement:

    Did you guys consider putting the hole in the piece of metal between the door and your floor installation?

    I have almost the exact same situation; I left the metal gap between the vehicle bed and the doors untouched but have a finished floor w/ trunk right inside. I’m wondering if there’s a reason you decided to drill through the finished floor rather than through that metal?

    Also, thank you guys so much! I’m almost finished with my 3 month build starting with 0 construction experience. You guys have been my heroes/muses/best teachers the whole way and I’ve studied your work religiously at every step. I’m so grateful!

  5. If you only installed the Scirocco fan or the floor vent/duct/inline fan, which would you do? Another way to put it, which helps the most to keep you cool on those hot nights? 😉 Thanks!

    • The floor vent is probably better because it lets cool air enter the van, but we use the Sirocco a lot because it can shoot in any direction… if we had to start over we would go for both!


  6. With this vent and the fan being in the front of the van do you feel like you get enough airflow in the sleeping area on a hot night? I’ve been trying to decide to mount the fan in the front or back of the van. Thanks

    • We get enough air flow, but during a hot day (full sun) with the dark van paint, it gets a little hot back there. (fortunately, we don’t really use the bed during daytime!)
      If you don’t plan on cooking in the front of the van, you could install the fan in the back of the van; we see more vans with this setup. In our case, we cook a lot in the van (because winter) so our forward fan is helpful.

      Hope that helps!

  7. In the first picture, is that a fan on the passenger side wall? If so tell me more. What model? Do you like having it there? Still helpful with the powered vent?

    Thanks, you’re really helping with our build!

    • We’re using it mostly as passive, but when it’s really hot we enjoy using the blower.
      We first try a computer fan, but we were somewhat disappointed with the performances and the noise (yep, there was an irritating sound).
      We like the blower because it fits perfectly into the duct.

      That’s pretty much it!

    • We would not idle the engine and leave the air intake open. We driving that’s not an issue (we’re aware there is low pressure in the back and fumes want to enter, but we’re still alive!).
      We first used the opening inside rear pillar, but there was too much restriction. Plus it’s easier to install a gate + a duct this way. Plus, if it gets REALLY hot we could open the gate + the 2 pillar openings.

      Good day!

  8. Ya might keep an eye on that blast gate. A buddy of mine uses the same ones for his wood shop, with a shop vac (much more suction), and he’s had them fall apart over time/use.


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