This incident was widely publicised, but it doesn’t look as though all caravan owners have heeded the message. A couple of days prior to Xmas, a video was uploaded to AussieCams showing dashcam footage of a solar panel coming adrift  from the roof of a caravan near Eastern Creek in Western Sydney on December 20.

The Winnebago Australia/Avida roof design requires a special frame assembly to mount the panels above the roof but tied to the 40mm sq tube that runs up each side of the roof and this will tie the solar frame and panels to the body frame. As for the 4 square corners to hold the panel on, there are also straight mounting designed to go along the straight edges of the panel and they should be used in multiples to increase the adhesion contact area, proper preparation and an SMP glue will attach these to the roof. For those with the floating skin roof, you need to find the timber bearers under the roof and attach the mounting to that, preferably by drilling a hole and sqirting a quantity of SMP adhesive to hold the roof to the timber frame under it, but if you must, a wood screw into the frame, lot of SMP adhesive to hold it in place and keep the water out will secure the mounting to the actual frame.

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Reg Watson, your knowledge of the RV industry appears to be lacking. There is nothing in the frame of the average caravan that could be bolted to that would give you the mechanical fasting you seem to consider a minimum requirement. Caravans are built from the inside out so the last thing attached is the outer skin. they are built this way so all the cabling and pipe work can be run through the walls. There is no access to the underside of the frame. The frame is either 10mm thick x 20mm wide pine, 1 mm tick aluminium tube or cold room wall panel construction that is two bits of thin aluminium sheet attached to a thick piece of polystyrene, there is nothing to bolt to and if you were to drill holes in the aluminium tube you are likely to cause the tube to crack at the fault line you have made causing the whole structure to be weakened. Adhesives have come a long way, so far that many high performance vehicle frames and chassis are actually glued together, The roof panel and front/rear windows in most production vehicles are glued on these days. The high speed trains have their panels glued on because the flexing and stresses would tear the panels around the mechanical fasteners. Adhesives add a level of elasticity that a mechanical fastener can not and that is why mechanical fasteners are not suitable for every application.

Sadly, recommending mechanical fixing of solar panels to the caravan roof is silly. The average caravan roof is made of a sheet of 1mm or less thick sheet of aluminium, a self taping screw is not going to hold anything much into a base material like that. A very well known motorhome manufacturer, Avida previously known as Winnebago Australia, have a rubber sheet membrane over am extremely thin sheet of 3 ply with polystyrene foam under that and the inside ceiling is a sheet of aluminium ….. unless the bolts went right through all those layers and could have a nut and washer fitted where the load could be spread, mechanical or adhesive fastening will not hold a solar panel securely on these roofs. Others have fibreglass panel roof material, about 2 layers thick, and I can assure you that a self taping screw will not hold the panels on that either …. I’m in the process of fixing one right now. Silicon seals holes and does that rather poorly, it does not glue things down very well at all. Poor preparation of the surface makes the adhesion even worse. The glue of choice is an SMP type adhesive, not affected by ultraviolet light and has a high temperature adhesion point. The aluminium roof or fibre glass roof requires a good adhesion area for the SMP adhesive to stick and we recommend full length aluminium angle with a foot minimum width of 25mm, both faces roughed up to key the faces, cleaned up with the appropriate solvent, that allowed to dry and a good bead of adhesive applied that will spread out under the contact area and bead out along the edges, apply weight evenly along the contact face for 24hrs to allow a good cure thickness. It will take 7 days or more to fully cure, so high speed trips is not recommended inside the week, but the cured material will hold the uncured material in place without the weights still being required.

This is my last word on the subject because I am shaking my head at some of the comments in this column. A self-tapping screw you were considering ? I’ll have to remember that when I install my grand-daughter’s car seat.

I had a friend who was lucky that he had a dashcam. He had a set of pipes come off from a vehicle in front of him. The driver tried to deflect it wasn’t his fault. The dashcam proved otherwise. He was sued for damages to my friend’s car.

Ultimately, at the end of the day, the owner of any object coming off a vehicle/trailer/caravan will be subject to criminal charges for not ensuring the objects were secured correctly if causes injury or death to a person.

But it’s not just social media providing bad advice. When researching for the previous article on this issue, I came across a number of Australian web sites advertising solar panel corner mounting brackets for caravans claiming the brackets can be safely affixed using just a good quality silicone sealant/adhesive. A quick search this morning found this to still be the case.

Let’s face it, if the pressures were as extreme as you are trying to make out, the RV would explode into splinters as soon as a truck passed in the opposite direction …. and I’m sure you have seen the news footage of caravans that have rolled over, the strength of the frame is fairly obvious by the way they turn into a pile of match sticks when the hit the ground, so there are a lot of other structural forces involved that you have not considered. What must be noted is, not many moulded panel mounts can be glued straight onto the roof, they need a lot of preparation to get a good keyed surface for the adhesive to hold onto, the slick shiny surface does not provide that.

Use of the correct adhesive is very important. I installed 2 solar panels last year, one was attached with MarineFlex, the other with ArmourFlex. Both have ABS corner & side brackets. After that first incident, I checked my panels, and found the first one was starting to lift on one corner. I had to pull up hard, but it did come off. The second panel wouldn’t budge, I even tried with a crowbar.

From what you are suggesting why on earth would you just attach a solar panel with adhesive only given you have no idea the wind forces involved that would be acting on the panel at 100 klm/hr ? The airflow over the top of the panel if exposed to wind forces is similar to that of an aircraft wing and produces reduced pressure above the panel which then has a natural tendency to lift. I don’t think Boeing rely on just glue to hold their wings to the airframe. We don’t glue solar panels to our rooves either.

My caravan came with wiring, and junction box on the roof, installed ready for solar, unless it was for Christmas lights.

Imagine being the owner of that caravan and arriving at your destination to discover the solar panel was gone. There would (or at least should) be some sleepless nights to follow.

There are plenty of caravans on the roads these days and many have solar panels on their roofs – but not all of these panels are properly affixed. This can result in disaster.

I don’t know if you’ve ever owned a caravan, or seen inside one. But the idea of having a “anchor point frame inside the vehicle to bolt into from the outside” is just not going to happen. Stuff like that needs to be incorporated at build time.

Back in October last year, we reported on a tragedy where three people died and four more were hospitalised after a driver lost control near Ross in Tasmania’s Midlands when trying to avoid a solar panel dislodged from a caravan.

It needs bolting down and into a proper support structure of the caravan or RV. If you want to glue as well as an extra precaution fine but bolting down will be the minimum required.

1. Real names are preferred - you should be happy to put your name to your comments.2. Put down your weapons.3. Assume positive intention.4. If you are in the solar industry - try to get to the truth, not the sale.5. Please stay on topic.

Caravan manufacturers will need to incorporate additional structural support in the frames to allow solar panels to be affixed correctly.

I recognise that section of the road…. worse place for a solar panel to come off near a bridge on a 110km/h motorway (with minimum shoulders). I dare say what would have happened if a truck was there at the same time and there are lots of trucks that use that road.

Accidents don’t just “happen”, they are caused. Aside from the tragedy through potential loss of life or injury and the costs of damage involved, a solar panel not properly affixed and coming adrift could land the caravan owner in legal hot water as well.

“With the increasing number of home handymen doing their own work and so many social media sites often giving suspect advice from unqualified people, it is important that handymen do their research on the correct way and safely to attach their solar panels.”

I hope someone with a science background comes on here to back up my alarm as normally I am one of the last people to be alarmist except when safety is concerned. The fact that a serious accident (3 deaths) occurred in Tasmania should be enough for every regulatory authority in Australia to insist on solar panel mount safety inspections for every vehicle with them attached and help stamp out the back-yard DIY-selfers with their tubes of Bunnings silicones and glues.

Maybe the manufacturers should add some stucture in the roof. Not going to be easy, there’s so many different size panels available.

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I would be interested to read of the forces involved. Have any links? I can’t see the panel having lift anything like an aeroplane, otherwise wings would be made flat, with blunt leading edges.

This is frightening stuff. If the footage doesn’t make the bowels of owners of caravans with solar panels installed go all watery and inspire them to immediately check their vans (after a quick trip to the toilet), I don’t know what will.

Michael caught the solar power bug after purchasing components to cobble together a small off-grid PV system in 2008. He's been reporting on Australian and international solar energy news ever since.

Probably several items already on the roof would interfere with racks, and vice versa. Panels are usually placed where there is room (unlikely I know). Mine are: one behind an AirCon, and the other a large sunroof/vent. There’s a wind up TV antenna and an ensuite vent to avoid as well.

But when advertisers, mounting bracket manufacturers, YouTubers and others continue to provide bad advice, addressing the issue of caravan solar panel safety will be difficult and no doubt further close calls – and tragedies – will occur.

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A bit of common sense comes into play here – sticking a weighty device with a large surface area on the roof of van that could be travelling at 100 kilometres an hour, subjected to vibration and with air flow above and below the panel would suggest careful thought regarding fixing is required. This is really a job for a professional.

I’m sure the following NSW regulation about adding fittings that are not original manufacture equipment would be covered by this RMS document to warrant its roadworthiness.

I don’t think a caravan is classed as a vehicle, a motorhome or campervan probably is, but a quick read of the pdf seems only to mention mechanical mods, nothing about attaching solar panels.

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I contacted Selleys about the incident, and told them it was ABS mounts, so hopefully they will update the info on the cartridges and on-line. It does say to test first, so maybe I should have bought an extra mount and tried it out on the caravan first.

And as I said earlier, any adhesive will degrade over time when exposed to the elements. The combination of the wind against the panel trying to lift off coupled with extreme temperature variations, mechanical vibration during transit and UV/water exposure will all conspire together to weaken the adhesive over time. It will never be a permanent solution and will need constant checking. But, it’s your responsibility if the adhesive fails and something wrong happens, what will you have to say in court/police? Blame the adhesive company?

Come to think of it, roof racks are mechanically fixed to the roof of car. I’ve seen solar panels fixed to the roof racks. Why can the same be applied to caravans?

Another question is, will insurance cover you for property damage and/or personal injury if the solar panel came off. It would be scrutinised with a fine tooth comb and one.

For example, there are quite a few DIY videos on YouTube showing adhesive-only installations for mounting brackets, forgoing also mechanically fixing the brackets with screws.

I find it hard to believe you can’t find any structural anchor point. But even if that were true then it would simply be a matter of building an anchor point frame inside the vehicle to bolt into from the outside. As to references for the aerodynamics I don’t have time to go searching for studies specifically for caravans and RV’s but simple common sense tells you that when you force air over the side of an object then forces will be employed. Try reading about Jayco’s solution along the lines I just suggested. . https://www.caravancampingsales.com.au/editorial/details/caravan-solar-panel-fixture-warning-126938/

The use of the correct adhesive and proper surface preparation is the important part, the attaching force can often be greater than any mechanical fastener could achieve.

One more thing: I forgot to mention that the mounts came way from the adhesive, which is still firmly (mechanical removel needed) attached to the roof.

Did you even read my posts where I have said the 2nd panel is immovable, and the first panel’s adhesive is still attached?

Spoilers on cars/trucks are not glued on with adhesive, they’re bolted on. How would it be different for solar panels on caravans?

The question is what do caravan manufacturers think of this? Do they allow it that it meets the structural integrity of the frame?

People the forces involved on that panel are significant and the extent depends on a multitude of factors. As well I am sure many of you have felt the significant sideways forces when passed by a big truck or perhaps seen a heavy marquee tent lifted into the air like a feather when hit by a decent wind-gust. Well that sort of force is acting on the “glue-only” installation holding your roof-mounted solar panel – not to mention the wearing daily effects of UV, salt spray, flexing of the roof etc etc etc. You think because your panel is mounted flat on the roof of your caravan or RV that it isn’t being affected by upwards wind forces ? Think again.

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“There is nothing in the frame of the average caravan that could be bolted to that would give you the mechanical fasting you seem to consider a minimum requirement.”

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