Will Hail or Storms Damage My Solar Panels?

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For the vast majority of New Zealand homes, the honest answer is no: properly installed solar panels will shrug off our weather without a scratch. Quality panels are tested to survive hailstones of 25mm diameter hitting at around 80km/h under the international IEC 61215 standard that every reputable panel sold here is certified to. That is hail roughly the size of a $2 coin moving at motorway speed. New Zealand's worst hail events do occasionally exceed that, but panel damage remains genuinely rare. When storms do cause problems, it is far more often the mounting, the flashing, or a flying branch than the glass itself. The bigger financial risk is not the damage, it is finding out afterwards that your insurance and your warranty don't cover what you assumed they did.

Why this question matters more than it used to

Two things have changed. First, there is a lot more solar on Kiwi roofs now, so a single big storm puts a lot more glass in harm's way. Second, our weather is getting livelier. NIWA's climate monitoring has documented an increase in heavy rainfall and severe weather events, and the Cyclone Gabrielle and Auckland Anniversary floods of early 2023 reminded everyone that "it'll be right" is not a roofing strategy.

So it is a fair question to ask before you spend $10,000 or more bolting hardware to your roof for 25 years. The good news is that the engineering is genuinely robust. The part that trips people up is the paperwork, and that is where we'll spend most of our time.

What panels are actually built to survive

Every credible solar panel sold in New Zealand is certified to IEC 61215, the international design qualification standard. The hail test within it fires ice balls at the module to confirm it can take an impact without cracking. The baseline test uses 25mm hailstones at roughly 23 metres per second (about 83km/h).

Plenty of modern panels go well beyond that baseline. Many manufacturers now publish ratings for 35mm hail, and some premium modules claim resistance to hailstones of 35mm or larger by using thicker tempered front glass (typically 3.2mm) and stronger frames. If you live somewhere with a genuine hail history, this is worth asking about specifically.

Where panels really earn their keep is wind. Modules are rated for mechanical load, usually expressed in pascals, covering both the snow and wind pushing down on them and the suction lifting them up. A typical panel is certified to handle 2400 pascals of wind load (and many to 5400Pa of snow load). In plain terms, that comfortably exceeds the wind speeds a properly fixed roof will see in nearly all of New Zealand, including Wellington on a bad day.

The catch nobody mentions: the rating is for the panel, not the install

Here is the bit the brochures gloss over. That impressive wind rating assumes the panel is mounted exactly as the manufacturer specifies: clamped at the right points, on rails rated for the load, with the correct number of fixings into solid framing or purlins.

The single most common storm failure we see in New Zealand is not broken glass. It is panels or whole arrays lifting because the mounting was under-specified or the roof penetrations were done badly. A panel rated for 200km/h winds is worth nothing if it is screwed to a rail that pulls out of the batten in a 120km/h gust.

This is why the installer matters as much as the panel. The clever marketing wants you obsessing over the module brand. The thing that actually keeps your array on the roof in a southerly is whether the person fitting it engineered the mounting for your specific roof, wind zone, and the loads in the New Zealand Building Code (NZS 1170 covers structural loads, including wind). If you want to understand how the panels themselves are built and why some are tougher than others, we go through the hardware properly over here: https://nzsolaris.co.nz/your-guide-to-nz-solar-hardware-and-tech/.

How New Zealand's weather actually stacks up

The risk is not the same across the country, so it pays to be honest about your own patch.

Hail: Genuinely damaging hail is uncommon but not unheard of. Canterbury, inland Otago and parts of the lower North Island see the occasional severe hail event. NIWA records show large hail does fall here, but the storms big enough to threaten certified panels are rare and localised.
Wind: This is the real one. Wellington, the Wairarapa, Cook Strait districts, Canterbury's nor'westers and exposed coastal and rural sites all see wind that demands a properly engineered mount. A flat, well-fixed array on a low-pitch roof in a high wind zone needs more fixings than the same array in sheltered suburban Hamilton.
Heavy rain and flooding: Panels themselves are sealed and waterproof. The risk in a flood is to the inverter and any ground-mounted or low-level electrical gear. Cyclone Gabrielle damaged a lot of electrical equipment that sat too low.
Snow: Central Otago, the Mackenzie and alpine areas get snow loading. Modern panels handle it, and a tilted array sheds snow well, but the mounting again needs to account for the load.
Salt and humidity: Northland and coastal sites face corrosion more than impact. This is a frame, fixing and connector issue, not a glass one, and it is why marine-grade components matter near the coast.

The quiet damage you can't see: microcracks

Here is an insight that rarely makes it into a sales pitch. The dramatic storm damage (a smashed panel, a lifted array) is obvious and gets claimed. The sneaky one is microcracking: tiny fractures in the silicon cells caused by hail impact or flexing in high wind, invisible from the ground, that slowly drag down a panel's output over the following years.

This is exactly where the cell technology matters. The newer N-type panels are generally more resilient to microcracking and degrade more slowly than the older P-type modules that dominated the market for years. If you are weighing up panel types and want to understand why N-type tends to suit our conditions, we lay out the comparison here: https://nzsolaris.co.nz/n-type-vs-p-type-solar-panels-nz/. We also took a close look at a couple of the N-type options now common in New Zealand here: https://nzsolaris.co.nz/das-solar-tongwei-review-nz/.

The practical takeaway: after any serious hail or wind event, even if the panels look fine, it is worth having the system's output checked against its expected production. A sudden unexplained drop can be the only clue that a panel took a hit.

So what actually happens if a storm does damage your system?

This is where homeowners get caught out, so let's be very clear about who pays for what. There are three separate things that might cover storm damage, and they cover completely different problems.

1. Your house insurance (the main event)

Storm, hail, and wind damage to your solar system is almost always covered by your home and contents insurance, not by the panel warranty. Most New Zealand insurers treat a roof-mounted solar system as part of the building, the same as they would your roof or your spouting.

But "almost always" is doing some work in that sentence. The traps:

Tell your insurer you've installed solar. A $10,000 to $15,000 addition to your roof can change your sum insured. If you never declared it, an insurer can reasonably argue it was not part of the policy. A two-minute phone call after install protects you.
Check whether your policy is sum-insured. Most NZ house policies are now sum-insured (you nominate a rebuild figure) rather than full replacement. If your sum insured was calculated before you added solar, it may not stretch to replacing the array on top of rebuilding the house.
Watch the excess. A single damaged panel might cost less to replace than your excess, in which case a claim is pointless. Know your number before you need it.

Consumer NZ has long pointed out that under-insurance is one of the most common and costly mistakes Kiwi homeowners make. Bolting an expensive system to the roof and forgetting to update the policy is a textbook way to fall into it.

2. The product warranty (defects, not weather)

A panel's product warranty (typically 12 to 25 years depending on the brand) covers manufacturing defects: delamination, faulty cells, a frame that corrodes prematurely. It does not cover an act of God like hail or a tree through your roof. That is what insurance is for.

This distinction matters because installers sometimes blur it, implying the warranty has you covered for "anything". It doesn't. The warranty is the manufacturer promising the panel was built right; insurance is your protection against the world doing damage to it.

There is also a separate performance warranty, which guarantees the panel will still produce a minimum percentage of its rated output after a given number of years (often around 87 to 92 percent at year 25 for good N-type modules). This is where that microcrack risk reconnects: if a hail event quietly accelerates degradation, you may have a performance claim, but only if the manufacturer accepts the cause, which is rarely straightforward.

3. The installer's workmanship warranty

Separate again. The workmanship warranty from your installer covers the install itself: the mounting, the wiring, the roof penetrations. If an array lifts in a storm because the mounting was under-specified, that is a workmanship issue, and a good installer stands behind it.

This is the warranty most likely to actually get tested in a storm, because, as we said, bad mounting is the number one storm failure. A workmanship warranty is only as good as the company offering it, which is the whole argument for choosing an installer who will still be trading in ten years.

The thing that quietly voids your cover

Here is the trap worth its weight in gold. Both manufacturer warranties and your insurer can decline a claim if the system was not installed to the manufacturer's specification or to New Zealand standards.

If a cowboy installer used the wrong clamps, too few fixings, or mounted panels in a way the manufacturer doesn't sanction, then when the storm hits you can find yourself bounced between three parties: the panel maker says it's an install fault, the installer has folded or won't answer, and the insurer points to the dodgy workmanship as grounds to reduce or decline. You are left holding the bill.

The defence against this is entirely in your control at the buying stage:

Use an installer who provides a Certificate of Compliance (CoC) and an Electrical Safety Certificate (ESC) on completion. These are legal requirements, not optional extras.
Get the mounting system make and load rating in writing, and confirm it suits your wind zone.
Keep your full documentation: invoices, warranties, the CoC, and serial numbers of every panel. You will need these for any insurance claim.
Choose panels from a manufacturer with a real New Zealand presence, so a warranty claim doesn't mean emailing a factory overseas with no local accountability. We explain what the "Tier 1" label does and doesn't promise about that backing here: https://nzsolaris.co.nz/tier-1-solar-panels-meaning/.

A worked example: the Canterbury hailstorm

Picture a 1990s brick-and-tile place on the Canterbury plains with a 6.6kW array of N-type panels, fully installed for around $13,000. A severe nor'west storm rolls through with 30mm hail, larger than the panels' 25mm certified rating.

Most likely outcome: nothing. The panels are tilted, the hail mostly glances off, and the tempered glass holds. Output is checked afterwards and reads normal.

Worse case: two panels take direct hits and crack. Replacement of two panels plus the labour and a scaffold might run $1,500 to $2,500. If the homeowner declared their solar to their insurer and their excess is $500, they claim, pay the excess, and the insurer covers the rest as storm damage. Total out of pocket: the excess.

The bad ending: the homeowner never told their insurer about the solar, the install was done by an operator who has since vanished, and there is no CoC on file. The insurer questions whether the array was even covered and whether the install met standard. Now that $2,000 repair is a fight, and possibly a self-funded one. Same hail, same panels, wildly different result, decided entirely by paperwork done years earlier.

Who should think harder about this

Being straight with you: most homeowners genuinely don't need to lose sleep over storm damage. But a few situations warrant extra care.

Exposed high-wind sites: coastal Wellington, Wairarapa hill blocks, exposed Canterbury and Cook Strait properties. Pay for the engineered mounting and don't accept a generic spec.
Older roofs: if your battens or purlins are tired, the fixings have nothing solid to grip. A roof inspection before install is money well spent.
Coastal corrosion zones: Northland and seaside sites need marine-grade frames and fixings; ask specifically.
Flood-prone areas: mount the inverter and any battery well above likely flood levels. The panels will be fine; the electronics are the vulnerable part.

What to do next

If you already have solar, the homework is quick and worth doing this week:

Phone your insurer and confirm the solar system is declared and your sum insured accounts for it.
Dig out your CoC, ESC, warranties and panel serial numbers, and save them somewhere you'll find them.
After any big storm, compare your system's output against a normal day or its expected production. Quiet underperformance is the tell-tale of hidden damage.

If you are still shopping, build storm resilience into your buying decision: ask for the mounting load rating in writing, choose a hail-rated panel if you're in a hail-prone area, and pick an installer who'll be around to honour their workmanship warranty. If you want to sanity-check whether the whole thing pencils out for your roof before you go further, our cost and payback tool is a good starting point: https://nzsolaris.co.nz/solar-roi-calculator/.

Frequently Asked Questions

Can hail actually break a solar panel in New Zealand?

It can, but it is rare. Certified panels survive 25mm hail at around 83km/h under the IEC 61215 standard, and many premium modules handle 35mm. New Zealand's hail occasionally exceeds that, so damage is possible in a severe event, but for most homes it is an unlikely outcome rather than a regular worry.

Does my house insurance cover storm damage to solar panels?

Generally yes. Most New Zealand insurers treat a roof-mounted system as part of the building, so storm, hail and wind damage is covered the same way your roof is. The crucial step is telling your insurer you've installed solar and making sure your sum insured reflects it, otherwise a claim can get complicated.

Will the panel warranty cover hail or wind damage?

No. The product warranty covers manufacturing defects, not weather events. Hail and storm damage is an insurance matter, not a warranty one. Be wary of any installer who implies the warranty covers "anything", because it doesn't.

What is the most common storm damage to solar systems here?

Mounting failure, not broken glass. The most frequent issue we see is panels or arrays lifting in high wind because the mounting was under-specified or the roof fixings were poorly done. This is a workmanship problem, which is why the quality of your installer matters as much as the panel brand.

Can a panel be damaged without me noticing?

Yes. Microcracks from hail impact or wind flexing can be invisible from the ground while slowly reducing output over time. After any serious storm, it is worth checking your system's production against a normal day. An unexplained drop can be the only sign a panel took a hit.

Are some panels genuinely tougher than others?

Yes. Panels with thicker 3.2mm tempered glass and stronger frames carry higher hail and load ratings. N-type cells also tend to resist microcracking better and degrade more slowly than older P-type modules, which can matter over a 25-year lifespan in our conditions.

Do I need special cover in a high-wind area like Wellington?

You don't necessarily need special insurance, but you absolutely need an engineered mounting system designed for your wind zone under the relevant New Zealand structural loading standards. The panels can handle the wind; the question is whether the mounting and roof fixings can. Insist on the load rating in writing.

What happens to my solar in a flood?

The panels themselves are sealed and waterproof, so they're rarely the problem. The vulnerable parts are the inverter and any battery, which should be mounted well above likely flood levels. After events like Cyclone Gabrielle, the damage was overwhelmingly to low-mounted electrical gear, not the panels.

The bottom line

Storm and hail damage is one of the smaller risks of going solar in New Zealand. The hardware is genuinely tough, and certified panels handle our weather well in nearly all cases. The real exposure sits in two places: a mounting job done on the budget, with corners cut, and insurance and warranty paperwork that wasn't kept tidy. Get both of those right and a storm becomes a non-event.

If you take one thing away, make it the phone call to your insurer to declare your system and check your sum insured. It costs nothing and it is the difference between a smooth claim and a fight. And if you're still choosing panels, it's worth understanding why the cell technology affects durability over the long haul, which we cover when we compare N-type and P-type modules over here: https://nzsolaris.co.nz/n-type-vs-p-type-solar-panels-nz/.