Flat or gently sloped roof
A shallow slope traps more dust, pollen and debris than a steep roof, where rain naturally does part of the work.
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Soft brush, deionised water and a product made for photovoltaic glass: we clean your system panel by panel, then dry the glass with a squeegee. A simple step to get back the yield of a clean roof.
Why clean them
Dust, pollen, bird droppings or urban pollution build up in a fine layer on the modules — invisible from the ground, but very real on the active cell surface. On a shallow roof or near a main road, this gradual soiling can cost several percent of yield without any warning sign.
Done properly, cleaning gives the glass its active surface back without harming it: soft-bristle brush, deionised water and a product made for photovoltaics, never high pressure. Yield climbs again, and the check that follows spots what is hard to see from the ground.
Our approach
A quick phone call to assess your system: number of panels, roof height, access. We confirm whether your roof qualifies for the standard package.
Soft brush, deionised water and a product made for photovoltaic glass, panel by panel. We finish with a squeegee and an absorbent sleeve, so the glass dries mark-free.
Checking the mounting hardware, visible wiring, and any sign of corrosion. Any issue found is reported, with a service follow-up proposed if needed.
Before/after photos are sent once the job is done. With the CHF 399 package, the report also lists what the technical check picked up.
On site
The footage below comes from a real visit on a residential roof, from the first look to the final result.
Dust, pollen and moss along the roof edge build a continuous film on the glass. Up close, the active surface is no longer really black.
The brush works panel by panel, with a product made for photovoltaic glass. No high-pressure jet, no abrasive contact.
The deionised water carries away what the brush has lifted. With no limescale, it leaves nothing behind on the glass.
We pull the water off panel by panel with the squeegee. An absorbent sleeve then picks up the last drops, without scratching the glass.
05 · AfterSame roof, two hours later. The panel mirrors the sky again: the simplest sign of a surface handed back to the sun.
On this roof, access was safe to walk on. Depending on the setup, we work from the roof or from the ground with the telescopic brush.

Roof moss removal
On the job shown above, moss had settled along the modules. Cleaning removes it from the glass and frames. If the roof covering itself is overgrown, we offer full roof moss removal.
Once panels are mounted, the roof covering can't be reached without taking them down. Removing moss beforehand saves a return trip to the roof.
Moss holds moisture, lifts tiles and clogs gutters. Under a system built to last 25 years or more, the roof covering should start out clean.
Brushing, low-pressure rinsing and an anti-moss product suited to tiles, slate or fibre cement. Never high pressure, which damages tiles.
Roof moss removal and treatment
from CHF 1'800
Price confirmed at the technical visit, depending on area, pitch and access.
2026 pricing
The quote is confirmed after a short chat about your system. No hidden fees.
| Service | Price |
|---|---|
| Cleaning only (up to ~30 panels) | CHF 249 |
| Cleaning + technical check (inverter, mounts, cabling) | CHF 399 |
| Large roof (over 100 m²) | CHF 4 / m² |
| Complex access surcharge (tall roof, obstacle) | +CHF 90 |
| Roof moss removal with anti-moss treatment | from CHF 1'800 |
Who it's for
A shallow slope traps more dust, pollen and debris than a steep roof, where rain naturally does part of the work.
Traffic dust, agricultural pollen or urban pollution build up in a fine layer, invisible from the ground but measurable in your yield.
You don't walk past your system every day. We bring our own equipment and water, so there is nothing for you to prepare.
Soiling builds up gradually and is often underestimated. A check-up and cleaning confirms whether production still matches expectations.
Our commitment
FAQ
Yes, in most cases. A layer of dust, pollen or bird droppings reduces the active cell surface and can cost several percent of yield, more so in locally soiled spots (droppings, plant debris). The effect is stronger on shallow roofs and systems near a main road or farmland.
Once a year is enough in most situations in Western Switzerland, since rain provides partial natural upkeep. Two visits a year are recommended for flat roofs, dusty or agricultural environments, or after a heavy pollen spring.
No — quite the opposite: cleaning done properly (deionised water, soft brush, a product made for photovoltaic glass, no high pressure) is part of the standard care recommendations from most manufacturers. It's aggressive cleaning or an untrained operator that can cause issues.
In the vast majority of cases, no. Our telescopic equipment covers nearly all residential roofs (2 to 3 storeys). A surcharge only applies to tall roofs or very restricted access.
Late winter or early spring, before the summer production peak and after the period when pollen and debris build up the most. A second visit in late summer is useful if your surroundings are dusty.
No, if done correctly. Soft-bristle brush, deionised water and a product made for photovoltaic glass, then a squeegee to dry. No high-pressure jet, no abrasive contact with the panel glass.
A full clean of the system, followed by a technical check: inverter and error messages, mounts, visible cabling, condition of the modules. You get the photo report and the points to keep an eye on. Choose it if your system has not been checked for several years.
More questions about your solar system? Visit our solar panels page or our full FAQ.
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