Adding aftermarket window(s) to a Transit, Sprinter or ProMaster van conversion has many benefits and is totally doable by the average DIYer. Let’s dig deeper!
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First obvious role of a window is ventilation. A proper ventilation system normally have an exhaust and one/several intake(s):
MAXXFAN OR FANTASTIC?
The Maxxfan has an integrated cover that prevent rain from entering the van, even when the fan is running. On the other hand, the Fantastic is basically like a big hole-in-the-roof: its cover must be closed when raining. To compensate, the Fantastic has a sensor and will automatically close when it detects water. But it’s when it rains that controlling moisture and condensation is critical! From our experience, not being able to ventilate when it rains doesn’t make sense. For this reason, we highly recommend the Maxxfan.
The volume of air “removed” by the roof fan must be replaced by the same volume of fresh air, otherwise the ventilation system doesn’t work. In most cases, there is no fan to push the air inside: as the exhaust fan creates a negative pressure inside the van, air is “sucked” into the van by any intake available (windows, holes, cracks, etc.) This is referred as passive intakes.
Keep in mind that a passive intake offers resistance to air flow; too small and your intake won’t be effective (so your ventilation system)! Try it: close all intakes (windows, holes ,etc.) and you will hear the roof fan “force” as it cannot pull air outside.
Think of surface area: ideally the intake should have a similar area as the exhaust. For example, the Maxxfan exhaust is 12in diameter; that’s 113in2 surface area. It’s quite large, so a window is ideal as a passive intake. In comparison, a hole of 4″ diameter has 12.5in2 and a 4″ square has 16in2…
Adding a window helps controlling:
Thermal comfort for a person at rest is around 72±4F (22±2°C). While an air conditioning unit can be used to control ambiant temperature under extreme heat (actually, unless you have a generator or you are plugged to shore, it’s not too realistic for off-the-grid applications), ventilation can do it too under normal conditions for a fraction of the energy bill.
Indoor Air Quality
Indoor polluants can cause respiratory problems and proper ventilation help recycle the polluted air with fresh air.
Non-exhaustive list of polluants:
1.2- See The Outside World
B-U-T! There are a few things to keep in mind:
Small spaces are fast to clean, but they get messy in a blink of an eye. Trust us! When living in a van, the key to sanity is organization. Having multiple storage options all over the van is important, so that each thing has its own dedicated place and can be easily put back to where it belongs.
Windows reduce storage potential; it’s a trade-off. That being said, we could add windows without removing storage in our layout… Food for thoughts!
10 Neat Storage Ideas for DIY Van Conversion
Windows are the weakest link for heat loss. Each additional window reduces your insulation capacity and is an opportunity for a cold draft. So if you intent on using your van as a ski hut like us (faroutride.com/winter-vanlife), think twice before adding windows all around.
Finally, adding insulated window covers are a must to keep the van comfortable; it makes a HUGE difference, we can’t emphasis on that enough!
DIY Insulated Window Covers
Rear Door Windows
Number of times we removed the insulated window covers (faroutride.com/insulated-window-covers) from the rear door windows to look outside: ZERO.
And this seems to be a consensus among people that have a layout similar to ours (garage and raised bed). It’s romantic to think we wake up and look outside and stay in bed and all, but that just doesn’t happen in real life. If we want to see outside, we grab a coffee then go outside. In winter we get out of bed, grab a coffee and hang out by the “fireplace” (a.k.a. the Webasto faroutride.com/air-heater-installation) while looking through the sliding door window.
Bottom Word: If your van comes with factory rear windows, fine. But we personally think it’s not worth adding some if you have a garage + raised bed layout.
1.3- Window Location
Most folks position their roof fan towards the rear of the van. We personally cook (stove/oven) a lot inside the van during winter, so we positioned our roof fan towards the front of our van, near the kitchen range (faroutride.com/wedgewood-range-vision-review):
Ideally, you want your exhaust (roof fan) and you main intake (window) far apart from each others. The goal here is to create a draft that travels through the van’s length to optimize circulation and ensure air is recycled at every corners.
1.4- On Second Thought
Wait, what? Our “Second Thought” normally comes at the END of the article! Here’s what’s going on:
We did NOT add a window above our bed and, well, maybe we should have. The floor vent (faroutride.com/floor-vent) works OK, but it’s not good enough as passive intake; the in-line fan must run and is pretty noisy (note: it’s great as stealth ventilation in cities when we’re out of the van). Also, a window would be much more efficient at purging big volume of air (i.e. when driving).
We plan on adding a window during summer 2019 (Half-Slider Bunk on passenger side), so what comes next is planning rather than build documentation… we will update this article when the window will be added!
2- Window Options
CR Laurence (CRL) is without a doubt the most popular window option. Except for the half-slider, their design is “all-glass” so it looks very OEM. They also come with a detachable mosquito screen. We’ll go with CRL for sure!
3- Window Installation
We plan on installing a half-slider bunk window during summer 2019, so here is the planning:
Make the cutout –> Primer/Paint –> Install window from outside –> Install trim ring from inside –> Pilot screw locations –> Install all crews not fully tighten –> Tighten all around –> Test for water leak.
- The cutout template is created using the trim ring.
- We will consider using an electric metal cutter shear (amzn.to/2BjauUx) as it produces less debris than a jigsaw. (don’t think it can go through frames though)
- As usual, exposed edges (after cutting) must be painted to prevent corrosion.
- CRL Windows are clamped to the body of the van using a trim ring and a weather seal; no sealant is needed.
- It is recommended to pilot (make tiny holes) at each screw location.
- When clamping the window, a manual screwdriver should be used to prevent distortion of the trim ring.
Let us know if you have some recommendations before we do this!
Nice To Meet You.
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!