Do You Need Planning Permission for Solar Panels?

For the large majority of homes in England, the answer is no. Solar panels on a roof are usually classed as permitted development, which means you can have them fitted without applying to your council for planning permission. It’s one of the reasons a solar install can go from survey to commissioning in a matter of weeks rather than months.

That said, “usually” isn’t “always”, and there are conditions attached to permitted development that a badly planned array can fall foul of. Here’s what actually applies.

The permitted development conditions

For panels mounted on the roof of a house, the rules are specific and fairly easy to meet:

They can’t sit above the highest part of the roof, excluding the chimney. Panels go on the slope, not over the ridge.

They can’t project more than 200mm from the roof slope or wall surface. A standard on-roof mounting system with rails and hooks sits well inside this — it’s the sort of limit you’d only breach with a tilted frame designed to angle panels up off a shallow pitch.

On a flat roof, the equipment can’t be more than 600mm above the highest part of the roof. This is the condition that catches people out, because a tilted frame on a flat roof is exactly how you’d normally mount panels there. It doesn’t rule it out, but the frame height has to be designed around the limit.

The installation has to minimise its effect on the building’s appearance and on the amenity of the area, so far as is practicable, and be removed when it’s no longer needed.

Meet those and you don’t need to apply for anything.

Where the exceptions are

Listed buildings. Panels can’t go up under permitted development on a listed building or within its grounds. You’d need listed building consent, and likely planning permission too. It isn’t automatically a no — but it’s a conversation with the conservation officer before anything else.

Scheduled monuments. Same position: outside permitted development entirely.

Conservation areas and World Heritage Sites. This one is widely misunderstood. Roof-mounted panels in a conservation area are generally still permitted development, even on a roof facing the road. The restriction is on wall-mounted panels fitted to a wall fronting a highway. If you’ve been told you can’t have solar because you’re in a conservation area, that’s worth checking rather than accepting.

Flats and maisonettes. Permitted development covers blocks of flats as well as houses, but if you don’t own the roof, planning is the least of it — you’ll need the freeholder’s agreement first.

If you’re unsure where your property stands, your council’s planning pages will tell you whether you’re in a conservation area, and Historic England’s list will confirm a listing. When there’s genuine doubt, a Lawful Development Certificate from the council puts it beyond argument — useful evidence to have when you eventually sell.

The approval people actually forget

Planning isn’t the only permission involved. Every grid-connected system has to be notified to your Distribution Network Operator, the company that owns the local cables — not your energy supplier.

Systems up to 16A per phase (3.68kW on a single-phase supply, which covers most 6 to 10 panel arrays) fall under G98: fit and notify, with the paperwork submitted within 28 days of commissioning. Anything larger falls under G99 and needs the DNO’s permission before the system is connected, which can add a few weeks to the timeline.

With 460W panels, that threshold works out at around eight panels — so most 12 to 20 panel systems, and most solar-plus-battery installs, will need a G99 application. It isn’t a problem and it’s rarely refused, but it does need doing in the right order. Any MCS-certified installer handles this as standard; it’s not something you should be filling in yourself.

What this means in practice

A conventional array of 6 to 20 panels on a pitched roof, on a house that isn’t listed, is permitted development. No application, no fee, no delay. The two things worth checking early are whether the property is listed and whether the system size will trigger a G99 application — both are established at survey stage.

If your roof is flat, or your home is listed or in a conservation area, that’s exactly the kind of thing to raise before anyone quotes you. Our free, no-obligation survey covers the design and the notification side alongside the roof itself, so you’ll know what’s required before you commit to anything.