DIY vs professional solar panel cleaning: what is safe to do yourself

Updated 6 November 2026 · By the Solar Panel Cleaners team

Short answer: You can safely clean ground-mounted panels and panels you can reach from the ground with a soft brush and gentle water, ideally purified water, avoiding pressure washers, detergents and abrasive pads. Never climb onto a roof or stand on panels to clean them. For most rooftop arrays, a professional pure water clean from the ground, typically £80 to £180 for a house, is the safer and more effective option.

The short answer

DIY is reasonable when the panels are on the ground, on a low garden structure, or on a single-storey roof you can reach entirely from the ground with a pole. It is not reasonable if it means climbing a ladder onto the roof, leaning out of windows or standing on panels. Falls from height are one of the most common causes of serious injury in the UK, and a pitched roof wet with cleaning water is far more slippery than it looks.

DIY and professional compared

Factor	DIY cleaning	Professional pure water clean
Typical cost	Low once you own a brush and hose	Usually £80 to £180 for a house
Reach	Ground-mounted and low panels only	Most two and three-storey roofs from the ground
Water quality	Tap water can leave mineral spots	Purified water dries spot-free
Stubborn fouling	Hard to shift safely from the ground	Soaked and brushed with the right kit
Safety risk	High if any ladder or roof work is involved	Lower, as work is planned from the ground
Visual check	Limited view from below	Closer view of glass, frames and cabling

If you clean them yourself

Use a soft-bristle brush or a soft brush head on an extendable pole
Use gentle water from a hose with no pressure nozzle, or a bucket of clean water
Use no washing-up liquid, bleach, glass cleaner or solvents
Work early or late in the day when the glass is cool
Rinse from the top down so dirty water runs off the panel
Leave stubborn droppings or lichen soaking rather than scrubbing hard
Stop if you see cracked glass or loose cables and contact your installer

Tap water in hard water areas, which covers much of southern and eastern England, can leave white spots as it dries. That is cosmetic in small amounts, but a film of minerals can build up over repeated washes. Some people buy a small purifying filter for this reason, although for one or two cleans a year it is rarely worth the cost compared with a professional visit.

What never to use

Pressure washers or jet nozzles
Scrapers, blades or razor scrapers
Scouring pads, wire wool or abrasive sponges
Strong chemicals, bleach or moss killers on the glass
Squeegees with damaged rubber that can drag grit across the glass
Hot water on cold glass in winter or cold water on hot glass in summer

Many panel manufacturers publish cleaning instructions with their warranty documents. These typically advise soft brushes and clean water, and warn against high pressure and abrasive or chemical cleaners. Ignoring the manufacturer's guidance could give them grounds to reject a warranty claim for damage to the glass.

When a professional makes more sense

Panels are on a pitched roof above single-storey height
There is heavy bird fouling, lichen or moss
You need bird proofing as well as a clean
The panels have never been cleaned since installation
You want someone to look closely for damage or nesting
You have a large array, a flat roof or a commercial building

Common DIY mistakes

Most damage to panels from home cleaning comes from good intentions. People reach for whatever cleans the car or the windows, and that is usually the wrong thing for solar glass.

Mistake	What can happen
Using washing-up liquid	Leaves a film that attracts dust and can streak in sunlight
Scrubbing lichen hard	Scratches the glass or wears the coating
Using a pressure washer from the ground	Can drive water past seals and damage the coating
Climbing a ladder onto the roof	Risk of a serious fall and broken tiles
Leaning on or kneeling on a panel	Can cause microcracks in cells that reduce output over time
Cleaning at midday in summer	Water dries too fast and leaves marks

Microcracks are worth understanding. They are hairline fractures inside the solar cells, often invisible from outside, caused by pressure or impact. They may not affect output at first, but they can spread with heating and cooling and gradually cut generation. That is the main reason nobody, professional or homeowner, should put weight on a panel.

A sensible approach

Many homeowners combine the two. They keep an eye on generation figures and look at the panels from the garden or an upstairs window, rinse any reachable panels themselves now and then, and book a professional pure water clean every year or two, or whenever droppings or lichen appear. That keeps costs down without anyone taking risks on the roof.

If you do clean reachable panels yourself, keep a note of the date and check your generation figures over the next few sunny days. That tells you how much difference cleaning really makes on your system, and helps you decide how often a professional visit is worth booking.