Solar panel roofs
Can a roof with solar panels be cleaned?
A roof carrying panels can be cleaned, but the work goes around the array, never over it. Below: what is reachable, what is not, and who deals with the panels.
The short answer
Yes, a roof with solar panels can be cleaned, but the work is planned around the panels instead of over them. The tiles or slates beside and below the array are cleaned by hand in the usual way. The panels, their rails, their cables and the tiles hidden underneath are a different matter, and we leave those to the installer. Before anyone climbs, we agree with you exactly what the clean will and will not cover.
5 min read ยท Part of Roof cleaning
What can be cleaned around an array
The open tiles on either side of the panels, the rows below them and the whole of any slope that carries none can all be cleaned. Growth is lifted by hand with soft brushes, and the slope is then treated with a low-pressure spray of biocide. A high-powered jet has no place beside glass and cables, and the reasons it is left off any tile roof are set out in our answer on washing a roof without damaging it.
The gutters under the array are cleared at the end, because everything lifted from the slope lands there. Where the panels sit close to the eaves, the clearing is done by hand from a ladder or a platform, rather than by working across the panels.
We also look closely at the tiles around the edge of the array. Moss packed against a panel frame can hold damp against the tiles beside it, and a tile that has slipped next to a frame is easy to miss from the ground. Each of these is photographed and reported, so you see exactly what was there.
What stays untouched
Some parts of a solar installation are not ours to work on, and the clean is planned so that we never need to.
- The panels themselves, which have their own cleaning advice from the maker
- The rails and hooks that hold them to the roof
- Cables, connectors and the isolator switch
- Any tiles hidden beneath a panel
Walking on panels can scratch or crack them, so nobody steps on the glass. If the installer left written cleaning instructions, keep them to hand; if you have no record of them, the installer or the maker is the right place to ask.
Electrical work on the array is for the installer or a qualified electrician. Where we see something that looks loose or damaged, such as a cable hanging free or a frame that has shifted, we photograph it from a safe position and pass it to you rather than touch it. You can then take the photos to whoever fitted the system.
Where the installer is still in touch, a short call before the survey is worthwhile. They can confirm how the array is fixed, tell us if any part of the roof is off limits, and say whether the panels have a maintenance routine we should work around.
The tiles beneath the panels
Growth that has crept under a panel is the awkward part. Reaching it means lifting the panels off, which is an installer's job, and it can mean a call to the installer about disconnecting the array first. That is a separate piece of work, with its own cost, and we do not fold it into a roof clean.
If moss or debris does build up beneath a panel, the options are these:
- Leave it, and keep watching the edges for spread
- Ask the installer to lift the affected panels so the tiles can be cleaned
- Plan the clean for the next time the array comes off for other work
Which one makes sense depends on how far the growth has travelled, and a look from a ladder shows that better than a photograph from the ground. Leaves and debris trapped at the lower edge of a panel are the easiest to deal with, because they can be reached from below without disturbing anything on the roof.
Whichever option you choose, keep a photo of the area now, so that you can compare it in a year and judge whether the growth is spreading.
Planning the visit around the panels
A roof with panels is booked as a survey first. We look at which slopes carry the array, how the roof is reached, and whether any scaffold would stand on the public pavement, where a licence is needed. Where it is, we arrange the licence with our scaffolder.
The written price follows that survey and is one total, so you are not left guessing about the extra care the panels ask for. The wider job, from the moss to the gutters, is described on the main roof cleaning and moss removal page.
Panels are sometimes added to a roof that already needs attention. If tiles are cracked or flashings are lifting under or beside the array, the repair comes first and the clean afterwards, because getting at the tiles later means disturbing the panels again. A cleaned roof around the array also makes it far easier for an installer to see the roof when they come back for a service.
On the day, we keep the crew off the panels, cover or move anything on the ground below, and clear up as we go. You get photos of anything unusual we spotted at the edges of the array, so you have a record to show the installer if needed.
More questions
Will cleaning my roof affect the solar panel installation?
It should not. The panels, rails and cables are left alone, nobody walks on the glass, and the spray is kept off the array. If you have any doubt, tell us who fitted the panels, and we will ask them what they advise before the survey, so nothing is done that they would object to.
Who cleans the solar panels themselves?
That is for you and the installer. The maker gives cleaning advice for the glass, and the installer knows how the array is wired and fixed. Our job is the roof around it: the tiles, the gutters and the growth that has spread next to the frames and along the edges.
Tell us what's wrong with the roof.
You'll get one written total price.