Solar panels can often be installed without a full planning application, but the property's status and the equipment's position matter. Rules changed on 27 August 2026, separating several limits for houses from those for blocks of flats and adding provisions for plug-in solar. [1]
Panels on a house
For equipment mounted on a house or an associated building, the principal current limits include:
- Pitched roof: projection must not exceed 0.2m, measured perpendicular to the roof slope, and the equipment cannot rise above the highest roof point, excluding a chimney.
- Flat roof: equipment must not rise more than 0.6m above the highest roof point, excluding a chimney.
- Wall: projection is limited to 0.2m where the wall abuts a highway, or 0.4m otherwise. The amended rules also address balcony and roof enclosures. [2]
These measurements do not remove the need to minimise effects on appearance and local amenity, or the requirement to remove equipment when it is no longer needed. Check the proposed mounting arrangement, not just the panel's thickness. [2]
Do not transfer the house allowances to a block of flats. The legislation now sets out separate tests, and flat-roof installations in specified protected areas can require prior approval. Establish which building category applies before relying on a supplier's general statement about permitted development. [2]
Conservation areas and listed buildings
Being in a conservation area is not a universal prohibition on roof panels. However, the house-mounted right excludes equipment on a wall, balcony or roof enclosure that fronts a highway in a conservation area or World Heritage Site. Scheduled monuments and listed-house premises have separate exclusions. [1]
Listed building consent is needed for alterations affecting a listed building's special architectural or historic character. This is a separate question from whether planning permission is required. A sensitive panel location does not by itself establish that either consent can be omitted. [3]
For an application, the August 2026 NPPF recognises the benefits of energy-efficiency improvements and renewable energy through policy CC2. Heritage effects still require assessment under the heritage policies; national support for solar is not automatic approval for every historic roof. [4] [5]
Panels standing in the garden
For stand-alone solar at a house, the panel surface area must not exceed 9m². Apply the lowest relevant height limit:
- 1m where within 5m of the boundary and forward of the house's principal elevation.
- 2m where within 5m of the boundary, or in the specified conservation-area position nearer the highway than the house.
- 4m where no lower limit applies. [6]
Further exclusions apply in World Heritage Sites, listed-building curtilages and scheduled monuments. Prior approval must be considered for the specified conservation-area frontage locations and for installations on article 2(3) land within 5m of a boundary. Blocks of flats have a separate set of stand-alone conditions. [6]
Draw the array's position against the actual house, highway and boundaries. A garden installation cannot safely be assessed using roof-mounted rules, and meeting the area limit alone does not establish permission. [6]
Plug-in equipment and technical safety
The amended permission excludes specified plug-in solar installations on wooden or timber-clad surfaces. This is a planning limitation, not a general declaration that every plug-in product is electrically suitable for a home. [1]
Roof-mounted panels require assessment of the roof's capacity to carry the added load. Electrical work must meet the applicable requirements, with the appropriate certification arrangements. Ask for the structural assessment where needed, electrical documentation and clear handover information rather than treating a planning exemption as technical sign-off. [7]
The transition ends in August 2027
A narrow saving applies where equipment was permitted immediately before 27 August 2026 but ceased to be permitted solely because of the amendment. The order allows that previously permitted development until the end of 26 August 2027. It is not a general exemption from unrelated restrictions. Recheck any proposal relying on that saving before 27 August 2027. [1]