How to install campervan solar panels
Are you stressing about installing your campervan solar panels? We’ve been there. Installing large, breakable panels onto the roof of your pride and joy is rarely an enjoyable experience. There’s a lot at stake, and it’s worth taking your time and making sure it’s done correctly—after all, a good carpenter measures twice and cuts once.
In this guide, we’re going to discuss solar panel installation and arm you with the knowledge you need to make sure you don’t end up with any accidental water features.
We’ll cover the following:
- A quick recap on types of solar panels
- Getting acquainted with your van roof
- What equipment you’ll need to install your campervan solar panels
- Different types of solar panel mounts
- How to install the panels with z-brackets or corner mounts
- Flexible panel installation
- Installing your cable entry
Types of Solar Panels
There are 2 main types of panels we’ll consider mounting on our van today – rigid and flexible. Rigid panels tend to be the standard for campervan conversions due to their low cost and high durability. They’ll fit on most vans and usually offer the optimum solution.
On the other hand, flexible panels are more expensive but may be necessary if you’re working with an unusual roof shape (think retro airstream trailers or vintage VWs). For our full explainer, why not check out our introduction to solar blog.
What Type Of Solar Panel Can I Install On My Roof?
If you haven’t installed your campervan solar panels, roof fan or given it a deep clean yet, then there’s a good chance you’ve never seen the roof of your van. Disappointingly, it’s not a perfect, flat, smooth surface for you to work on. The roofs of most vans have lots of ridges running the length of the van to make things complicated, so you’ll have to plan carefully before getting started.
Rigid or Flat Campervan Roof?
We recommend getting well acquainted with your roof before buying any solar panels. The easiest way to do this is to take a tape measure and a camera to map out the grooves and see what space you have to work with. This way, you’ll know the maximum dimensions of the roof and, more importantly, the space between the grooves where you have to mount your panels.
We recommend getting well acquainted with your roof before buying any solar panels. The easiest way to do this is to take a tape measure and a camera to map out the grooves and see what space you have to work with.
This way, you’ll know the maximum dimensions of the roof and, more importantly, the space between the grooves where you have to mount your panels.
Single or Multiple Panels?
One large solar panel or two smaller ones. A 360W solar panel can measure up to 2m long. If you’re a solo converter, you’ll need a friend or two to help with the solar installation.
A single large solar panel might take up less space than two smaller panels with the same output wattage, but installation can be much easier.
Now that we’ve considered the size of the solar panels, we need to discuss mounting methods…
Solar Panel Mounting Options
Once you’re happy with your roof space and what solar panels your van can accommodate, you’ll have to consider how to mount them.
Z-Brackets vs Corner Mounts
Z-brackets are supplied as standard with all rigid-panel solar packages, such as this 350W solar system. However, if you prefer corner mounts, please let us know, and we can swap them.
If your van is fitted with a roof rack, you will also have other options. However, we don’t feel this is necessary, so if you don’t already have a roof rack, we don’t recommend buying one to mount your solar panels.
Z-Bracket and Corner Mount Sizes
Z-brackets are often the cheapest method of attaching solar panels to your campervan roof. They are easy to install and sit almost flush with your campervan roof.
Z-brackets will add about 20mm to the width and length of your solar panel when attached.
Corner moults can often be more expensive than z-brackets and add 30mm to the height profile of your campervan. Some people don’t like this look as it’s less stealthy than the z-brackets.
Others don’t like corner moulds because glueing something to your roof sounds scary when driving at 70mph on the motorway.
Corner mounts will also increase the size of your solar panel by 60mm in each direction. Again, this must be considered before purchasing.
Does my Solar Panel Type Influence my Mounting Method?
Yes it does…
Suppose you’ve opted for a rigid solar panel. In that case, you can attach it to your campervan roof using z-brackets or adhesive corner brackets. Alternatively, a flexible solar panel can be glued directly to your roof.
What Else Should I consider For Solar Panel Mounting?
Remember to consider your roof fan and solar cable entry at this stage. Although smaller than your solar panels, you may want to position the fan in a particular place, such as above the kitchen or bed, for ventilation.
How To Install Campervan Solar Panels
Now that we understand the following:
- What type and size of the solar panel is suitable for my van
- Which solar panel mounting technique do I prefer
We can begin installing our shiny new solar panels on our campervan roof.
Z-Bracket Installation for Rigid Solar Panels
When considering installing z-brackets, remember they will add about 20mm to the width/length of your solar panel where attached.
What You Will Need:
- Solar panels
- 4 brackets per panel (6 for panels > 175W)
- M5 bolts and locking nuts, ideally 316 stainless steel (2 per bracket)
- M5 penny washers
- 5mm metal drill bit
- SikaFlex 221
- A friend to help
You’ve hopefully figured out exactly where your solar panels will fit on your roof, so now it’s time to install them.
1. Start by fitting the brackets to your solar panel frame. You’ll need to drill a small hole for the bolts to fit through.
2. Bring one of your solar panels onto the roof of your van and position it to be installed.
3. Use a pencil to mark through the bracket holes to the van roof, making sure the panel doesn’t move as you make your way around all the brackets.
4. Remove the panel from the roof and prepare for drilling. We recommend masking tape and bin bags to catch all the metal filings produced when drilling – these are a nightmare for inducing corrosion.
5. Drill through the van roof using your 5mm metal drill bit for each bracket.
6. Bring the panel back onto the roof, laying a generous amount of SikaFlex 221 sealant underneath the brackets.
7. Attach the panel to the roof using the M5 bolts and penny washers from the roof side, with another washer and locking nut from inside the van – you’ll need your friend to help here.
Corner Mount Installation for Rigid Solar Panels
Remember corner mounts will increase the size of your solar panel by 60mm in each direction.
What You Will Need:
- Corner mounts
- Side mounts for panels larger than 175W
- SikaFlex 221
- Rubbing alcohol
SikaFlex 221 is the industry standard and is designed for use on metalwork for caravans. It’s therefore the perfect choice for campervan conversions.
1. Start by bringing all panels and corner mounts onto the roof of your van and arranging them how you plan to install them. Ensure the corner mounts fit flat on the roof and are not uneven due to the ridges in the van roof.
2. Mark where the mounts will be positioned and remove the panels from the roof
3. Clean the area where the mounts will be positioned with rubbing alcohol – this encourages good adhesion.
4. Use SikaFlex 221 to attach the mounts to the roof, leaving it to dry as per SikaFlex guidance.
5. Once you’re happy the SikeFlex is set, bring the panel onto the roof and position them on the corner mounts. You’ll now need to drill through the mount to secure the panels.
Flexible Solar Panel Installation
Flexible solar panels are easy to install and require being glued to the van’s roof. Therefore, we usually only recommend installing flexible solar panels on flat roofs, which are common on the VW T series. This ensures the best mounting surface.
- Clean the roof around where the solar panel(s) will be placed thoroughly, ideally with rubbing alcohol (this will help to promote better adhesion).
- Using Sikaflex, securely fix the roof mountings and leave them dry.
Cable Entry into Campervan
The next task for your solar panel installation is to bring the cable into your van. We have written about the importance of MC4 Connectors, so check that out before going any further.
To bring your solar cables inside, you’ll have to drill yet another hole in the roof. To do this, follow the easy steps below
- Bring your solar entry gland onto the roof of your van and choose where it will be positioned. Its location should be selected to minimise cable length from your panels to the gland, but it must also be flat to form a good seal. Mark this location.
- Drill a 10mm hole in the centre of your gland location.
- File the edges of the hole, be careful to collect any metal shavings, and give it a Hammerite coating to protect it from corrosion.
- Once the Hammerite is dry, insert a rubber grommet in the hole to protect your cables, you can also use a short length of flexible conduit if you want.
- Route your cables into the entry gland and through the rubber grommet to the inside of the van.
- Use SikaFlex 221 to secure the gland to the roof of your van, making sure to leave it time to set before driving.
Running Cables from your Solar Panel to MPPT
You’ll need to run cables from your solar panels to your MPPT. This is pretty self-explanatory, but we always like to remind you that the cable run is probably longer than you think in a van.
We must consider the horizontal and vertical distance the cable needs to run to get to the MPPT because nothing is simple like everything else in the campervan conversion.
To do this, we need to measure the total distance the solar cable will travel before it reaches the MPPT.