Solar rarely makes the news in our world, but a change landing this month is worth a look — especially if you specify PV on new homes or advise clients on what they can install without a planning application. On 27 August 2026, a new order rewrites the permitted development (PD) rights for domestic solar in England, and for the first time writes plug-in “balcony” solar into the rules.
What’s actually changed
The change comes via The Town and Country Planning (General Permitted Development) (England) (Amendment) Order 2026 (SI 2026/896), which was made on 29 July 2026, laid before Parliament on 30 July, and comes into force on 27 August 2026. It amends Part 14 (renewable energy) of Schedule 2 to the 2015 GPDO — the part that grants planning permission for certain solar installations without the need for a planning application.
The headline structural change is that the rules for dwellinghouses and for blocks of flats have been separated out and set down explicitly, where the old text bundled them together. On top of that, the order adds a set of clearer dimensional limits and — the genuinely new bit — a definition and rules for plug-in solar.
Solar on houses: the new limits
For solar PV or solar thermal on a dwellinghouse (Class A), the order spells out when an installation falls outside permitted development and therefore needs a planning application. The limits to have in mind:
- On a wall: not permitted if the equipment protrudes more than 0.2 metres beyond the wall where that wall abuts a highway, or more than 0.4 metres in any other case.
- On a balcony or roof enclosure: the same 0.2 m (fronting a highway) / 0.4 m (otherwise) protrusion limits.
- On a pitched roof: not permitted if it protrudes more than 0.2 metres beyond the roof slope, or if the highest part sits above the ridge (excluding the chimney).
- On a flat roof: not permitted if the highest part is more than 0.6 metres above the highest part of the roof (excluding the chimney).
- Heritage constraints: in a conservation area or World Heritage Site, not permitted on a wall, balcony or roof enclosure that fronts a highway; and not permitted at all on a scheduled monument or on a listed dwellinghouse.
Stand-alone (ground-mounted) solar in the curtilage (Class B) gets its own height table — ranging from 1 metre where it sits forward of the principal elevation and within 5 m of the boundary, up to 4 metres in the most unconstrained case — plus a cap keeping the panel area to no more than 9 square metres, and a new prior-approval step for stand-alone solar placed on article 2(3) land within 5 m of the boundary.
Plug-in “balcony” solar is now in the rules
The most talked-about change is the arrival of plug-in solar — defined in the order as solar PV “intended for connection to the relevant domestic premises’ electricity installation by means of a standard plug and socket”. It’s now folded into the definition of solar PV, which brings the plug-in, stand-it-on-your-balcony kits that are common across Europe into the English PD framework as they become legal to self-install here.
There’s an important safety-driven limitation, though: plug-in solar is not permitted development where any part of it would be installed on a wooden wall, balcony, fence, gate or enclosure, or on a timber-clad part of a house or block of flats. So the combustible-substrate carve-out that assessors already recognise from other parts of the regs shows up here too.
The one-year grace period
If you have a scheme or product that was permitted under the old wording but no longer qualifies under the new rules, the order includes a transitional provision: previously permitted development can still be carried out until the end of 26 August 2027. That gives roughly a year of overlap rather than a hard cliff-edge — useful if something is already designed and in the pipeline.
Why this matters for Part L and the Future Homes Standard
This is a planning change, not a Building Regulation — but it lands right next to the energy work we do. Under the Future Homes Standard, on-site solar PV is a central part of how new homes hit their Part L targets; the FHS notional dwelling assumes a meaningful area of roof-mounted PV. So the PD rules that govern where and how PV can go on a roof, a wall or the ground directly shape what’s deliverable on a plot without a separate application — and, by extension, how easily a design reaches compliance.
The practical takeaways are straightforward: if you’re specifying roof or wall-mounted PV, sense-check the new protrusion and ridge-height limits early so the array you’re relying on for the Part L result is actually permitted development; watch the heritage and listed-building carve-outs on constrained sites; and if plug-in kit is in the mix, keep it off timber substrates.
Solar is only ever one lever in the Part L calculation — the fabric, glazing and thermal-bridging numbers have to be right underneath it, or the PV ends up compensating for losses you could have designed out. If you’d like the fabric and PSI-value side modelled properly so your renewables aren’t papering over a weak envelope, get in touch and we’ll tell you how we’d approach it.
Sources: The Town and Country Planning (General Permitted Development) (England) (Amendment) Order 2026 (SI 2026/896), legislation.gov.uk · Explanatory Memorandum to SI 2026/896, legislation.gov.uk · Town and Country Planning (General Permitted Development) (England) Order 2015, Part 14 of Schedule 2, legislation.gov.uk