Van Build / 8th Feb 2022

Van Roof, Fans, and Solar Panels

Most of the van build is things I can always rip out and redo if I really screw them up, and that is a helpful thing to reassure me as I go along. When it comes to cutting holes in the van roof, though - that's not something you can really turn back from if you do it wrong, so I had to tread carefully here.


Butyl Sealant Tape
Buy From
Home Depot

Any place with roofing materials should have this.

Silicone Sealant
Buy From
Home Depot

Make sure you get one appropriate for metal roofs, like the advanced one. Lap sealant is also fine (it's more waterproof and more permanent).

Primer and Paint
About $30

Pop down to your local car parts store and get the right colours for your vehicle!

Roof Rack

Low Pro Roof Rack
Buy From
Flatline Van Co

I also got the extra front fairing.


MaxxAir 6200K Fan
Buy From
Camping World

There's several models - I picked the mid-range.

Solar Panels

Newpowa 180W Panels
$175 each
Buy From

I bought two, but the choice here is mostly about dimensions.

8 AWG Solar Panel Cables
Buy From

These go from the Y-connectors down into the van.

Solar Y Connectors
Buy From

The panels come with short cables each, so this bridges them in parallel to the main cables.

Cable Entry Gland
Buy From

Provides a waterproof cable entry point. Loads of options for these.

1010 Series T-Slot Flat Brackets (8)
$8 each
Buy From

I used these to connect the solar panels to the roof rack crossbars, but there are cheaper options!


Peplink Mobility 42G
Buy From

The rest of the networking gear will be in a future article!


Caulking Gun
Buy From

It's worth paying that little extra for a nice smooth one!


Any reasonably powerful cordless jigsaw will do (I use DeWalt 20V tools). Make sure it has a metal-cutting blade!


You'll want a nice set of bits in various sizes that are rated for light metal work, too.

Roof Rack

Before I cut any holes, I installed the roof rack - partially because I would need it anyway to mount the solar panels, but also so I could make sure it would be clear of the fan and the antenna locations.

The Ford Transit has built-in mounting holes along the roof for a roof rack - one on each structural rib, on each side. That means that you can buy pre-made roof racks that require no drilling - I opted for the Low Pro Roof Rack from Flatline Van Co., which is really nicely made and also uses standard 10-series extruded aluminium for the crossbars (so it's easy to mount things to it).

The roof rack is relatively easy to install with the instructions it comes with:

  1. Peel off the rubber plugs that cover up the M8 mounting holes on the roof.
  2. Install the ten brackets, with their neoprene pads and sealing washers to help prevent water ingress.
  3. Run an extra bead of silicone around the base of the bracket for extra water protection.
  4. While you have the silicone out, also waterproof the remaining rubber plugs as the paint that protects them will crack and let water in otherwise.
  5. Bolt the side rails to the brackets (and the two pieces of each side rail to each other), keeping everything loose.
  6. Slide the crossbars in, and bolt everything together.

It's really not that bad! The worst part is having to climb up and down a ladder and move it around the edge of the van a lot to get to everything - if you have a lower roof, or want to clamber on the roof itself, that would make that bit a lot easier.

Cutting Holes

The rest of the items require cutting holes in the roof, and there's a general method I followed that tries to keep the risk of rust and water ingress low:

  1. Measure twice - or thrice! I generally measured locations from both on top of the roof and inside the van to make sure there were good clearances, particularly bearing in mind the structural ribs and the roof rack.
  2. Make an initial hole with a small diameter drill bit.
  3. Enlarge the hole with successively larger drill bits until it's either big enough for a cable, or big enough to then enlarge further with a jigsaw or hole saw.
  4. Deburr the edges of the hole with a file.
  5. Add a coat of primer and two coats of paint over the bare metal edges to prevent them rusting.
  6. Mount whatever you're installing to the hole with a layer of butyl rubber rope sealant under it to prevent water ingress.
  7. Finally, finish around the outside of the item with silicone (or lap) sealant for a second waterproofing layer. Add sealant on top of any exposed screws too.

You can never have enough waterproofing, and you really don't want rust happening where you can't see it!

Ventilation Fan

The ventilation fan is by far the biggest hole, and requires additional consideration as to where you put it. There's generally two locations:

With my choice of fan at the front - both because of the shower/kitchen, as well as wanting to follow the Ford BEMM guidelines in case I ever install a heavier unit - I also needed to ensure I'd get airflow throughout the van.

This is doable on any van by drilling ventilation holes in the floor at the rear and adding mesh/ducting to them, but on the Transit I have it's even easier, as the D-pillar has a pre-made hole on the bottom that you can pull the plastic plug out of, and openings from the pillar into the cargo area just above the bed height. Add a little mesh and protection to the hole to stop insects and road dust, and maybe a little ducting, and you have your full-van airflow.

There's also the choice of which fan to go for - thankfully, they pretty much all fit a 14x14 inch hole in the US at least, but I opted for the MaxxFan, since a large number of other van builders seem at least mostly happy with theirs after a year or two, and the design means it's easy to replace the fan unit itself as it has a separate mounting flange.

With the location decided, marked, and clearances triple-checked, it was time to cut the hole. Before I started with the actual cutting, though, I made a test hole and jigsaw cut in the middle of the piece I was about to remove - after all, you're not going to have it on the van after this, may as well make it useful.

With the practice cut done, I then proceeded to drill out the four corners, and then do the straight cuts between then with the jigsaw. I wore eye and face protection during this as tiny metal shards go everywhere - and had a drop cloth over my nice floor to protect it.

With the hole made and protected from rust with paint, the remaining steps are:

And then you should have a fan! I also ran some spray foam around the inside to protect everything else against the sharp screw tips poking out where there wasn't any wood blocking, as well as to provide a little insulation and further waterproofing.

Solar Panels

The solar panels need two main pieces of work - cables run inside the van to where the electrical systems will be, and to be mounted onto the roof rack itself.

The cable positioning was chosen to be relatively close to the electrical area (over the left rear wheel well) while also being under the panels, to provide additional protection against rain. The two panels are connected in parallel, so there had to be room underneath the panels on the roof to wire the panels up to Y connectors before a single positive and negative cable work their way through the roof.

You'll also need some extra cables to go down through the roof holes - these need to be sized appropriately for the current and voltage (I went with 8 AWG in case I ever add more panels), and you want them to terminate in MC4 connectors on the roof side. I bought a set with MC4 connectors on both ends and cut the connectors off one end (be careful about which end to cut - I bench-assembled the panels, connectors and cables before I then cut the loose ends).

Where the cables actually enter the roof, you want a cable entry gland that provides the actual waterproof seal, as the cable will be loose in the actual hole and won't seal well. These are relatively cheap to buy and install, thankfully.

So, when I knew where I wanted my cable entry holes, I:

  1. Drilled out two holes big enough for the 8AWG cables.
  2. Primed and painted them to prevent rust.
  3. Added a plastic grommet to prevent the cable rubbing against the sheet metal (but you should use a rubber grommet really!)
  4. Threaded the cables through the entry gland and then the holes.
  5. Secured the gland onto the roof with butyl rubber and then silicone (no screws in this case - we'll see if it holds, but it feels very secure!)

At this point, I had connector ends on the roof, waterproofed on their entry down into the van. Now it's time for the panels themselves.

The roof rack I chose is standard 1010 series aluminium extrusion, so I got some rectangular plates (1x2 inches) with two mounting holes and the appropriate nuts/bolts, and mounted the solar panels with those:

  1. Decide on the orientation and positioning of the panels so you know where the crossbars of the roof rack will be.
  2. Drill holes in the solar panels if there aren't any where you need them - I wanted to mount mine on the short edge and their only holes were on the long edges, so I had to add some holes.
  3. Mount the plates to the solar panels with loose T-nuts on the other holes on the plates.
  4. Move the solar panels to the roof of the van (careful on that ladder now!) and plug them into the Y-connectors for parallel wiring.
  5. Slide the crossbars over the loose T-nuts on the plates so the panels are loosely attached.
  6. Place the crossbars onto the side rails and bolt down.
  7. Tighten up the bolts on the plates, and you're done!

The Low Pro rack has a slot along the sides so you can choose where the crossbars go, which helps immensely in making everything fit nice and tightly. There's also room on the roof still to mount a few more solar panels either side of the fan in future, if I want to.

As for the choice of panels themselves? I just got the biggest reasonably-priced ones that would fit on the roof, in this case a pair of Newpowa 180W ones that some other folks have had success with. I may also add the ability for more ground-standing panels in future, via a plug in the rear of the van.

LTE Antenna

Wave your phone around all you like, the only real way to get better mobile signal in the middle of nowhere is more gain on your antenna, and that means two things - a bigger antenna, and having it outside the giant metal box that is the van body.

I chose to install a Peplink Mobility 42G, which, while pricey, has decent reviews and appears to be an actual antenna rather than a circuit board in a plastic housing like some of the cheaper options, including multiple antennas for different LTE bands, as well as WiFi and GPS ones in case you want those too. It'll be hooked up to a Mikrotik LTE wAP router that I used to run the workshop off before I started paying Comcast too much money for Real Internet.

Installation here is rather easy comparatively:

  1. Cut the hole in the roof with a hole saw, prime and paint
  2. Place butyl rubber under the antenna around the hole, thread its cables through and place it on the roof
  3. Secure it from underneath with the giant nut that fits around the stem
  4. Run a bead of silicone around the outside of it once it's secured in place

An initial speed test of it seemed to look good, but it'll be hard to judge truly how well this performs versus my phone until I take the van for its first trip into the Rockies.

You can see even more blog posts about the van build on its category page, and get updates via my YouTube channel, Twitter, or blog RSS.