Planning Rules for Garden Solar Panels

Stand-alone ground arrays: the rules changed on 27 August 2026

In England, a stand-alone solar installation in the garden of a house is often permitted development under Class B of Part 14 of the General Permitted Development Order, rewritten on 27 August 2026. The panel area must not exceed nine square metres, and the height limit depends on where the array stands: four metres in most of the garden; two metres within five metres of a boundary; one metre if it is within five metres of a boundary and in front of the main elevation of the house; and two metres in a conservation area if it would be nearer a bounding highway than the house. It is not permitted development within the curtilage of a listed building or on a scheduled monument, and on a World Heritage Site it may not sit nearer a bounding highway than the house or within five metres of the boundary. Two cases need the council's prior-approval decision on appearance before work starts: a conservation-area array nearer a bounding highway than the house, and an array within five metres of the boundary in a conservation area, National Park, National Landscape, the Broads or a World Heritage Site. The array must be sited to minimise its effect on the area and removed when no longer needed. Miss any limit and you are not in a grey zone — you need planning permission.

The old rules were stricter, and older guides still quote them: until 27 August 2026 a house could have only one stand-alone array, it had to sit at least five metres from every boundary, and no dimension could exceed three metres, which ruled out most small gardens. Those three limits no longer apply to houses; they still apply in the grounds of a block of flats. Where PD fails, the consent route is unglamorous but reliable: a planning application (£258 in England for works in a house's garden), drawings showing siting and heights, and a case officer who mostly weighs neighbour amenity and street scene. Applications are usually decided within eight weeks, so start before ordering anything. Full design detail for this route lives on the ground array page.

Panels on garden buildings: the generous one

Solar mounted on a shed, garage, garden room, or other outbuilding is treated like roof solar on the house: often permitted development provided panels project no more than 200mm from the roof or wall surface, do not sit higher than the highest part of the roof (excluding chimneys), and the listed-building and conservation-area conditions are respected. There is no nine-square-metre cap on this route — which produces the useful quirk that a large shed roof can lawfully carry more PD solar than the lawn beside it. The catch is that the building itself must be lawful: an outbuilding that crept over its own PD limits when built cannot launder panels into legitimacy. If the garden room went up without the scrutiny it needed, resolve that first.

Pergolas and canopies: the ambiguous one

A solar pergola is assessed both as a garden structure (height limits: typically 2.5 metres within two metres of a boundary, more further in) and as a solar installation, and councils differ on which lens leads. Because the structure exists to carry the panels, some authorities read it as a stand-alone solar installation and apply the nine-square-metre logic; others treat it as an outbuilding with panels on top. This is the one garden solar route where we recommend a written LPA view as standard practice rather than caution — a short pre-application enquiry, often free for householders, settles it before steel is ordered.

Wales, Scotland, Northern Ireland — and the catches everywhere

Wales runs a similar PD framework with its own measurements; Scotland's regime differs more substantially, particularly on stand-alone installations; Northern Ireland's differs again. If you are outside England, treat every figure above as illustrative only. And in all four nations, three catches override the general rules: Article 4 directions (councils can strip PD rights street by street), planning conditions on your own house's original consent (common on newer estates — check your deeds pack), and restrictive covenants, which are a legal matter rather than planning but sting identically. None are exotic; all are findable in an afternoon.

How to actually confirm

Email your Local Planning Authority's duty planner with a one-page sketch: array or structure position, dimensions, distances to boundaries, and a note of any designations. Ask whether they consider the proposal permitted development, and keep the reply. For certainty that survives a house sale, a Lawful Development Certificate (around £129 for a proposed use in England) turns "we think so" into a document. It is rarely necessary for a four-panel array — but for a pergola, or anything near a boundary dispute, it is the cheapest insurance in the project. Then the fun part: budgets on the costs page, and a sense-check of your whole plan via the contact form whenever you want one.