Solar photovoltaic panels have become a mainstream choice for UK homeowners wanting to reduce energy bills and carbon footprint. The planning position for domestic solar is generally permissive, with most roof-mounted installations qualifying as permitted development.

Permitted Development for Solar Panels

Under Class A of Part 14 of the General Permitted Development Order, the installation of solar photovoltaic equipment on a dwellinghouse or a building within the curtilage is permitted development, subject to conditions. The principal conditions for roof-mounted panels are that they must not protrude more than 200mm from the roof slope or wall surface when installed, must not be installed on a roof where the panels would be higher than the highest point of the roof, must not be installed on a wall or roof that faces onto and is visible from a highway in a conservation area, must not be installed on a listed building or within the curtilage of a listed building.

For ground-mounted panels, the permitted development conditions include that the installation must not exceed four metres in height, must not be forward of the principal elevation of the dwelling, and the combined area of all ground-mounted solar equipment must not exceed nine square metres. Ground-mounted panels are not permitted development in conservation areas at all.

Conservation Areas

In conservation areas, roof-mounted panels on a roof slope or wall that faces onto and is visible from a highway require planning permission. This restriction is designed to protect the character and appearance of conservation areas. Panels on rear roof slopes that are not visible from any highway are still permitted development in conservation areas. In practice, most conservation area homes can install panels on their rear roof slopes without planning permission.

Listed Buildings

Solar panels on listed buildings or within the curtilage of a listed building are not permitted development. Planning permission and listed building consent are both likely to be required. Applications for solar on listed buildings are considered on their merits by the local planning authority, taking account of the heritage significance of the building and whether the panels would unacceptably harm its character.

Building Regulations

Solar panel installations do not typically require Building Regulations approval in their own right, but the electrical installation connecting the panels to the building's electrical system must comply with Part P and should be carried out by a registered electrician who can self-certify the work. The structural integrity of the roof to carry the panel weight should be checked by a structural engineer or the installer, particularly for older roofs.

Summary

Most domestic roof-mounted solar panel installations are permitted development and do not require planning permission. Conservation areas restrict panels visible from a highway to those on non-highway-facing roof slopes. Listed buildings require planning permission and listed building consent for any solar installation. Ground-mounted panels have their own permitted development conditions and are not permitted development in conservation areas. Electrical installation always requires Part P compliance.