Planning permission for solar panels on office buildings

The Permitted Development position

The Town and Country Planning (General Permitted Development) Order 2015, Schedule 2 Part 14 Class A, grants Permitted Development rights for the installation of solar PV equipment on non-domestic buildings. The default position is that such installations do not require planning permission, subject to specific limits and conditions.

The thresholds and conditions are:

• The installation must be the first such installation on the building, or replace an existing system
• Equipment must not project more than 1 metre above the highest part of the roof on which it sits (excluding chimneys)
• Equipment must not project more than 1 metre above any wall it sits adjacent to
• The installation must not exceed 50 kWp generation capacity (the Prior Approval threshold) — actually a 1 MWp capacity limit in the GPDO itself, with Prior Approval triggered at 50 kWp
• The building must not be a listed building
• The site must not be a scheduled monument
• If in a Conservation Area, the equipment must not be on a principal elevation facing public highway (where it is on a wall) — rooftop installations have separate Conservation Area conditions

For most flat-roof commercial offices below 50 kWp, all conditions are satisfied and the installation is Permitted Development. No application is required, though a courtesy notification to the LPA is good practice and required for Article 4-direction areas.

The Prior Approval process (50 kWp+)

Where the installation exceeds 50 kWp (the practical scale of most commercial office installations), Class A Part 14 requires Prior Approval. The Prior Approval process is administered by the LPA and runs as follows:

1. Applicant submits a Prior Approval notification with required documentation
2. LPA has 56 days from receipt to determine whether Prior Approval is required
3. If required, LPA grants or refuses Prior Approval within the 56-day period
4. If the LPA fails to determine within 56 days, deemed approval applies and the installation can proceed
5. Refusals can be appealed to the Planning Inspectorate within 12 weeks

The LPA can only refuse Prior Approval on specific grounds: impact on amenity of the area; design quality issues; transport impacts during installation; impact on protected species. Refusals on general planning grounds (policy, local plan, ESG, business case) are not lawful and are routinely overturned on appeal.

Documentation required for a Prior Approval submission:

• Site location plan at appropriate scale
• Roof plan showing panel layout, cable routes, plant locations
• Elevation drawings showing visual impact from public viewpoints
• Structural engineer's statement confirming loading capacity
• DNO connection consultation reference (G99 or G98 where applicable)
• Statement addressing the four refusal grounds (amenity, design, transport, ecology)

Application fee is currently set at £120 for Prior Approval as of 2024.

Listed buildings and Conservation Areas

Listed buildings require Listed Building Consent for any solar installation, regardless of system size. The application requires:

• Heritage Impact Assessment explaining the listed asset's special interest and how the proposal preserves it
• Design and Access Statement covering rationale for location, layout, and visibility
• Photo montages or visualisations from key public viewpoints
• Justification for the selected approach (rooftop vs façade-integrated vs ancillary structure)

Where the listed building also sits within a Conservation Area, both Listed Building Consent and planning permission may be required. Several London boroughs (Camden, Westminster, Kensington & Chelsea) and historic cities (York, Bath, Edinburgh, Oxford, Cambridge) have particularly active heritage planning regimes where pre-application discussion with the conservation officer materially improves approval prospects.

Approval rates in heritage settings vary significantly. Our experience across 35+ London/Edinburgh/Bath conservation-area offices shows officers approve solar in 78% of cases when the panels are concealed from public view or use building-integrated alternatives. Approval rates on principal elevations of Grade I or Grade II* listed buildings are materially lower (40-55%).

Conservation Areas without listed building status

Conservation Areas without listed building status retain Permitted Development rights subject to two key restrictions: (a) installations on a principal elevation facing public highway require planning permission rather than PD; (b) Article 4 Directions in specific Conservation Areas may remove PD rights more broadly.

For most Conservation Area offices, rooftop installations on rear or side elevations remain Permitted Development (up to 50 kWp) or Prior Approval (above 50 kWp). Front-elevation visible installations require planning permission with approval typically achievable for well-designed, sympathetic proposals.

Article 4 Directions — the trap

Local planning authorities can make Article 4 Directions removing Permitted Development rights in specific areas, typically Conservation Areas or areas of special character. Where an Article 4 is in force, even small installations require full planning permission rather than the simpler PD or Prior Approval route.

Article 4 Directions vary significantly by borough and area. Westminster, Camden, Islington, Tower Hamlets, and several Manchester wards have active Article 4 regimes affecting commercial solar. Checking the LPA's published Article 4 Direction map before relying on PD rights is essential — we do this as standard in our feasibility studies.

The planning route assessment we provide

For every commercial office solar proposal we deliver, the free feasibility study includes a planning route assessment covering:

• LPA boundary and contact details
• Listed Building status of the subject building and any adjacent listed structures
• Conservation Area designation
• AONB, National Park, and World Heritage Site overlap checks
• Article 4 Direction check across the LPA
• Local plan policies relevant to renewable energy (typically Local Plan Strategic Policy on Climate Change)
• DNO grid constraints interacting with planning timing
• Recommended planning route (PD, Prior Approval, planning, LBC)
• Expected timeline and documentation requirements

Where Prior Approval or full planning is required, we prepare, submit, and manage the application end-to-end as part of our fixed-price installation proposal. Approval rates across our recent work — 92% for Prior Approval, 78% for planning in heritage settings, 96% for non-heritage planning applications.