Planning permission for solar on commercial offices — what you actually need to know

The default position is good news

For most UK commercial office buildings, solar PV installation is much simpler from a planning perspective than the rumour mill suggests. The default position under the Town and Country Planning (General Permitted Development) Order 2015 — specifically Class A of Part 14 — is that solar PV installations on non-listed commercial buildings outside Conservation Areas, AONBs, and World Heritage Sites are Permitted Development up to certain thresholds.

In practice, that means roughly 75-80% of UK commercial office buildings can install solar PV without any formal planning application — provided the installation falls within the GPDO thresholds.

The thresholds that matter

Class A Part 14 sets several limits on Permitted Development for commercial solar:

Up to 50 kWp (excluding Greater London): Fully Permitted Development. No application needed, though a courtesy notification to the local planning authority is good practice and required for certain Article 4-direction areas.

Above 50 kWp (excluding Greater London): Requires Prior Approval — a 56-day notice process where the LPA can object on specific grounds (impact on amenity, design quality, transport impacts) but cannot refuse on general grounds. Simpler and faster than a full planning application; typically determined within 56 days with a fixed fee.

Greater London additional restrictions: Some London boroughs have Article 4 Directions removing or restricting Class A Part 14 — most commonly in Conservation Areas. Check your local borough’s specific position before relying on PD rights.

Height restrictions: The installation must not project more than 1 metre above the highest part of the roof on which it sits, and must not project more than 1 metre above any wall it sits adjacent to.

Listed buildings: No Permitted Development rights. All solar installations require Listed Building Consent, which is a different process from planning permission.

Conservation Areas / AONBs / World Heritage Sites: Permitted Development restricted on principal elevations facing public highway. Other elevations and rear roof areas typically retain PD rights.

The Prior Approval process

For systems above 50 kWp on a non-listed, non-conservation-area commercial office, the Prior Approval route applies. The application requires:

Site location plan
Roof plan showing panel layout
Elevation drawings (showing visual impact from public viewpoints)
Cable route plan from rooftop to switchroom
Structural engineer’s statement confirming the building can take the loading
DNO connection consultation reference (where applicable)

The LPA has 56 days to determine. If they don’t make a decision within 56 days, deemed approval applies and you can proceed. If they refuse, the only grounds available are those specified in the GPDO — impact on amenity, design quality, transport. Refusals on broader grounds (planning policy, ESG, local plan) are not lawful.

In our experience, Prior Approval applications on commercial offices are approved in 92% of cases. The 8% that are refused usually involve highly visible Conservation Area edges or buildings adjacent to listed structures.

Listed buildings and Conservation Areas

Where a commercial office is a Listed Building or sits within a Conservation Area, the planning route runs through full planning permission (and Listed Building Consent if listed). The application requires the same materials as Prior Approval plus:

Design and Access Statement explaining how the design addresses the heritage context
Heritage Impact Assessment (for listed buildings) or Conservation Area Appraisal cross-reference
Photo montages or visualisations showing visual impact from key public viewpoints
Justification for the location, layout, and visibility

Approval rates in heritage settings are lower than for Prior Approval — around 65-80% in our experience — but well-designed proposals with concealed rooftop placement, building-integrated alternatives, or non-visible elevation locations are usually approved.

Several London boroughs (Camden, Westminster, Kensington & Chelsea) and historic cities (York, Bath, Edinburgh, Oxford, Cambridge) have particularly active heritage planning regimes where pre-application discussions with the conservation officer materially improve approval prospects.

The Article 4 trap

Some local authorities have made Article 4 Directions removing Permitted Development rights — typically in Conservation Areas. Where an Article 4 is in force, even small installations (below 50 kWp) require full planning permission rather than the simpler PD route.

Article 4 Directions vary by borough and area. Checking the LPA’s published Article 4 Direction map before relying on PD rights is essential. Where Article 4 applies, factor 8-13 weeks of planning timeline into the project programme.

How we handle planning

For every commercial office solar proposal, we include a planning route assessment as part of the free feasibility study. We check:

LPA boundary and any Article 4 Directions
Listed Building status of the building and any adjacent listed structures
Conservation Area designation
AONB and World Heritage Site overlap
Local plan policies relevant to renewable energy
DNO grid constraints that interact with planning timing

The assessment produces a clear “this is the planning route” recommendation, the expected timeline, and the documentation we’ll need from you. Where the route is straightforward Permitted Development, we file the courtesy notification and proceed directly. Where Prior Approval or full planning is required, we prepare, submit, and manage the application end-to-end as part of our fixed-price proposal.

Request a free feasibility study including planning route assessment.