22 July 2026

Warranty and insurance when cleaning solar panels: how it works

Cleaning the wrong way can cost you more than leaving the dirt. Who is liable for what, and what does your warranty say?

The question behind much hesitation about cleaning is not "does it help?" but "does my warranty allow it?". The honest answer: proper cleaning yes, improper cleaning no. With osmosis water and a soft brush the coating stays intact and the glass dries streak-free: no manufacturer objects to that. The risk sits in the wrong tools: a pressure washer, aggressive detergents or scrubbing dry panels can scratch or attack the coating, and damage from a wrong cleaning method is exactly the kind of damage that leads to disputes with a manufacturer.

So before your first visit, consult the warranty terms of your panel brand: what manufacturers do and do not allow differs per brand, and what your terms say outranks any rule of thumb in an article like this one. Also keep the invoices of cleaning visits: being able to show later that the panels were professionally maintained puts you in a stronger position in any warranty conversation.

It helps to keep three layers apart, because when damage occurs you want to know whom to address. The factory warranty covers the panel itself and runs via the manufacturer. The installation: frame, roof penetrations, cabling, is the domain of your installer and their warranty terms. And the cleaning work itself falls under the liability of the cleaner who performs it. Three parties, three counters: sort that out beforehand and you lose no weeks to being passed around when something breaks.

Then that last layer: liability when you have it done. The companies receiving requests via this site are vetted on their Chamber of Commerce registration and their business liability insurance: damage caused during the work falls under it. If something does go wrong during a cleaning visit, always report it directly to the company and record it with photos. If you cannot resolve it together, let us know.

Ask a company three things before the first visit. One: the method: osmosis water and a soft brush, no pressure washing and no detergents. Two: confirmation that the work is covered by their business liability insurance. Three: photos before and after the visit, so the condition of the panels is on record. Serious companies find none of these questions odd: anyone who bristles at them has answered your question already.

Meanwhile, build your own file: one folder with the handover documents of the installation, the warranty terms, the invoice of every visit and the before-and-after photos. If you discover damage, report it immediately: the longer you wait, the harder it is to show when it occurred, and that timing is exactly what determines who is on the hook. A complete file turns a he-said-she-said conversation into a matter of leafing through.

If you clean yourself, things are different: damage you cause yourself is in principle your own risk. How your home or contents insurance treats self-inflicted damage to your system differs per policy: check that beforehand rather than afterwards. It is one more reason to limit DIY to what is safe and low, and to leave all climbing and roof work to an insured professional.

Finally, the reverse question: can not maintaining hurt your position? That too is a matter of your own terms. Some warranty and insurance conditions assume normal maintenance of what is insured or guaranteed: how that is worded for your system you will only find in your own paperwork. The through-line of this whole story is therefore not case law but a habit: clean properly, have it documented, and read the terms properly once.

What does that insured work cost? A cleaning visit costs € 4 to € 8 per panel (€ 75 to € 175 for an average home), and if the professional spots loose cables or a shifted panel, such minor repairs fall under € 95 to € 250 per job. Request several quotes and set them against the price index: for the same roof, prices vary widely.