Solar panels on a pitched roof: permission and policy

Solar panels on a pitched roof of a house are usually permitted development, which means no planning permission is needed, provided the panels project no more than 0.2 metres beyond the plane of the roof slope and no part of the installation sits higher than the highest part of the roof, excluding the chimney. That right is in Class A of Schedule 2 Part 14 to the Town and Country Planning (General Permitted Development) (England) Order 2015, and it applies to front roof slopes as well as rear ones.

Two things routinely catch people out. The right carries conditions as well as limits, so siting has to minimise the effect on the appearance of the building. And it does nothing at all for a listed building, where consent is needed whatever the order says.

The right and its limits

Class A of Part 14 covers the installation, alteration or replacement of solar photovoltaic or solar thermal equipment on a house or a block of flats, or on a building within the curtilage.

For a pitched roof the two dimensional limits are the ones above: 0.2 metres of projection measured from the roof plane, and nothing above the ridge. In-roof systems, where panels replace tiles and sit flush, comfortably satisfy the projection test and are worth considering where the roof is visible. On a flat roof the limits change, with a maximum height above the roof surface and a minimum distance back from the external edge, so read the current text rather than applying the pitched roof figures.

Measure the projection to the highest point of the assembly, including the mounting rail and any clamp, not to the glass. A standard on-roof frame on battens over existing tiles can approach the limit on a low-profile roof covering.

The order has been amended several times since 2015, including changes aimed at making domestic and commercial renewable installation easier. Check the consolidated version on legislation.gov.uk before relying on a figure from an older article or a supplier's brochure.

The conditions attached to the right

Limits say what you may build. Conditions say how, and breaching a condition removes the right just as surely as exceeding a limit.

Class A requires that, so far as practicable, the equipment is sited to minimise its effect on the external appearance of the building and on the amenity of the area. It also requires the equipment to be removed as soon as reasonably practicable when no longer needed for microgeneration.

That first condition is why panel layout matters. A rectangular array set square to the eaves and ridge, with consistent margins and no panel straddling a hip or a valley, reads as a considered installation. A scattered layout working around a soil vent pipe does not, and gives an officer something to write about if a complaint arrives. Where a single panel would have to sit oddly, leaving it out is usually the better answer.

Conservation areas and World Heritage Sites

Roof-mounted panels on a house in a conservation area or a World Heritage Site remain within Class A, including on the slope facing the street. This surprises people, and it surprises some conservation officers.

What the order restricts in those areas is wall-mounted equipment: solar equipment must not be installed on a wall which fronts a highway. So panels on a side or rear wall may be permitted while the same panels on the street elevation are not.

Two caveats. An Article 4 direction can withdraw Part 14 rights street by street, and a number of authorities with large conservation areas have made them. And the condition about minimising effect on appearance still applies, so in a terrace of uniform slate roofs an in-roof system in a dark frame is a materially easier conversation than a silver-framed array on brackets.

Listed buildings and the separate consent

Permitted development rights do not displace listed building consent. Works to a listed building that affect its character as a building of special architectural or historic interest need consent under the Planning (Listed Buildings and Conservation Areas) Act 1990, and fixing panels through a historic roof covering will usually meet that test.

Expect the discussion to cover visibility from public vantage points, whether an alternative location exists on an outbuilding or at ground level, the fixing method and its reversibility, and what happens to the original covering. An ancillary building in the curtilage, or a garage roof hidden behind a boundary wall, often solves the problem.

A short Heritage Statement setting out significance, impact and justification does most of the work. Other microgeneration technologies raise their own consent questions, and the position for solid fuel is set out in our note on biomass boilers in a smoke control area.

Ground-mounted arrays

A standalone array in the garden falls under a separate class in Part 14, with its own limits on height, surface area, proximity to the boundary and the number of installations per curtilage. There are additional restrictions on land within the curtilage of a listed building and on designated land where the array would be visible from the highway.

Those limits are tighter than most people expect, and a garden array sized to run a heat pump will often exceed them. Where it does, a householder application is the route, and the matters in play are overlooking, loss of garden space, glint towards neighbouring windows and the appearance of the frames from the street.

Glint, glare and neighbour objections

Glint and glare is a genuine technical issue near aerodromes and on schemes affecting highway sightlines, where an assessment may be required. On a domestic roof it is almost never a sustainable objection.

Objections based on the appearance of panels carry some weight in a conservation area and very little outside one. Objections based on loss of a view carry none, because there is no right to a view in planning terms. The one neighbour issue worth taking seriously is overshadowing of an existing array, which is a civil matter rather than a planning one and is not protected by any right to light.

Where the works are permitted development, none of this arises, since no application exists to object to. That is a reason to check the limits carefully rather than to apply for permission you do not need.

The roof itself

Planning is the easier half. The roof structure has to carry the load, and that is a Building Regulations question under Part A rather than a planning one.

Three checks before ordering.

1. Have the rafter size, spacing, span and condition assessed, particularly on a roof with cut timbers rather than trusses, and on any roof previously re-covered with a heavier tile.
2. Confirm how the fixings penetrate the covering and how the weathering is made good, because most leaks on retrofit installations come from the flashing rather than the panel.
3. Check whether the electrical work will be notified under a competent person scheme or to building control, and keep the certificate with the house papers.

For new build and major refurbishment the policy picture is different again, with Part L of the Building Regulations and local plan carbon policies setting what the scheme has to deliver. That is the territory of an Energy Statement rather than a householder permitted development check, and overheating interacts with it on upper floors, as our piece on overheating in roof level and mansard flats explains.

If the panels sit within the limits, keep the supplier's layout drawing, a photograph of the finished installation and a note of the projection dimension. A lawful development certificate is available where a buyer's solicitor wants formal confirmation. Enter your postcode on PlanScope to see whether your property sits in a conservation area or carries other constraints.

This is general guidance, not legal advice: check the position with your local planning authority or a qualified professional before relying on it. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.