Do factories need planning permission for solar panels?
The Quick Answer
Most UK factories in England do not need planning permission for rooftop solar panels. Permitted Development Rights under Class A of Schedule 2, Part 14 of the Town and Country Planning (General Permitted Development) (England) Order 2015 (GPDO) allow solar panels on industrial and commercial buildings without a planning application — provided certain conditions are met. However, listed buildings, buildings in conservation areas, National Parks, Areas of Outstanding Natural Beauty (AONBs) and other designated land require additional scrutiny and may require full permission. Scotland, Wales and Northern Ireland have separate planning regimes with similar but not identical rules.
The question of planning permission is one that factory owners frequently misunderstand — either assuming they always need it (and wasting months and money on applications that are unnecessary) or assuming they never need it (and installing systems that technically require consent). Getting clarity on your specific site's status before engaging an installer is time well spent.
This guide focuses on the position in England. If your factory is in Scotland, Wales or Northern Ireland, the broad principles are similar but the specific permitted development thresholds and conditions differ — consult your local planning authority or a planning consultant with devolved jurisdiction experience.
Permitted Development Rights for Industrial Buildings (Class A)
Permitted Development (PD) rights are a standing consent granted by Parliament through the GPDO that allows certain types of development to proceed without needing to apply for individual planning permission from the Local Planning Authority (LPA). For solar panels on commercial and industrial buildings, the relevant provision is Class A of Part 14 of Schedule 2 to the GPDO 2015 (as amended).
Under Class A, solar PV and solar thermal equipment can be installed on a building if all the following conditions are met:
Condition 1: The building is not a listed building or scheduled monument
PD rights under Class A do not apply to listed buildings (Grade I, II* or II) or scheduled monuments. These require Listed Building Consent and potentially full planning permission. If in any doubt about whether your building is listed, check the Historic England National Heritage List for England (NHLE) at historicengland.org.uk.
Condition 2: The installation is not on a site within Article 2(3) land
Article 2(3) land includes conservation areas, National Parks, the Broads, Areas of Outstanding Natural Beauty (AONBs), and World Heritage Sites. In these locations, Class A PD rights are either withdrawn or subject to additional conditions. Factories within conservation areas face the most common complication — see the dedicated section below.
Condition 3: Panels do not protrude more than 200mm beyond the plane of the roof
This is straightforward for flat roof ballasted systems — most flat-roof industrial solar installations protrude more than 200mm from the flat roof itself but are measured from the plane of the roof slope (if pitched). Ballasted systems on flat roofs typically have panels tilted at 10–15 degrees to optimise generation — the height of these above the roof surface varies but is generally 200–600mm at the rear edge. The 200mm measurement applies to the extent of protrusion beyond the roof surface plane, not total height above roof level. Confirm the specific interpretation with your LPA for flat roof installations.
Condition 4: Panels are not installed on a wall that fronts a highway
Solar panels installed on the vertical face of a wall that directly faces a public highway (road, footpath, public right of way) require planning permission. For factories with panels on roof slopes or flat roofs, this condition is generally met unless you are proposing façade-mounted panels on a street-facing elevation.
Condition 5: Panels do not protrude above the highest part of the roof structure
Panel installations must not sit higher than the highest point of the existing roof structure (excluding chimneys, lift overruns, or other roof-mounted structures). For flat-roof industrial buildings with parapets, this typically means panels cannot be mounted so that their top edge exceeds the height of the parapet or plant room. This condition can affect the tilt angle achievable for large systems and must be checked at design stage.
Condition 6: Reasonable steps are taken to minimise the effect on the amenity of the area
This is a broader condition requiring that installations do not cause material harm to amenity — for example, excessive glare affecting neighbouring residents or roads. In practice, modern solar panels have anti-reflective coatings and this condition rarely causes issues for industrial rooftop systems, but it is a material consideration if your factory is immediately adjacent to a residential area.
Important: Lawful Development Certificates
You are not legally required to obtain a Lawful Development Certificate (LDC) to confirm that PD rights apply to your installation. However, getting one provides formal legal certainty that the development is lawful. This is strongly advisable for high-value installations — mortgage lenders, insurers, and future buyers will benefit from the certainty an LDC provides. The fee in England is approximately £234 (2026 fee schedule) and the determination period is 8 weeks.
When you DO need full planning permission (conditions that remove PD)
The following situations will require a formal planning application to your Local Planning Authority, regardless of how otherwise straightforward the installation may appear.
| Scenario | Why PD Does Not Apply | Likely Outcome |
|---|---|---|
| Listed building (any grade) | Class A explicitly excludes listed buildings; Listed Building Consent also required | Possible with sympathetic design; non-visible elevations preferred |
| Conservation area (Article 2(3) land) | PD rights restricted; Class A conditions modified for Article 2(3) land | Likely approved if roof not visible from public highway; case-by-case |
| National Park or AONB | Article 2(3) land; heightened landscape sensitivity | Requires careful design justification; generally supportable |
| Panels on highway-facing wall | Explicit Class A exclusion for highway-fronting walls | Likely approved if visual impact is acceptable |
| Article 4 Direction in force | Local planning authority has removed PD rights for specific area or property type | Varies; check local policy and design codes |
| Ground-mounted system exceeding 9m² or 4kW (on domestic curtilage) | Separate Class I rules apply to standalone ground-mounted systems | Likely approved for industrial use if EIA screening confirms minor significance |
| Large ground-mounted system (over 50kW or 1 hectare) | May constitute EIA development under Schedule 2 of the EIA Regulations | EIA screening required first; most under 5MW approved |
Note that Article 4 Directions — a mechanism by which LPAs can withdraw PD rights in specific areas — are increasingly being used by councils seeking to manage development in sensitive areas. It is worth checking with your LPA whether any Article 4 Directions affect your site before assuming PD applies.
Conservation areas and listed buildings — extra hurdles
Conservation areas and listed buildings represent the most significant planning complication for factory solar projects. Understanding the distinction between the two — and the additional requirements each imposes — is essential.
Conservation Areas
In a conservation area, solar panels on a roof slope that fronts a highway or is visible from a public highway are excluded from Permitted Development rights. The key test is visibility from the public highway — if your roof is not visible from any public road or footpath, Class A PD rights may still apply. However, this is a matter of judgment and the LPA will assess visibility based on site conditions.
Where a planning application is required in a conservation area, the LPA will consider the impact on the character and appearance of the conservation area. Modern solar panels with dark-coloured frames and anti-reflective glass have a lower visual impact than older-generation panels and are generally viewed more favourably. Flat-to-roof systems and in-roof systems are preferred over bulky framed systems where possible.
Practically speaking, many conservation areas contain light industrial and commercial buildings that are not particularly sensitive in character — a standard industrial unit within a conservation area is a different planning proposition to a Georgian townhouse. Context matters significantly, and a well-presented application can succeed in most non-historic industrial conservation area contexts.
Listed Buildings
For listed buildings, both Listed Building Consent (LBC) and planning permission are required. LBC is assessed against the impact on the building's special architectural or historic interest. The decision-maker must balance the public benefit of renewable energy generation against the harm (if any) to the heritage asset.
In practice, solar installations on listed industrial buildings are not inherently unachievable. Historic England published guidance in 2022 emphasising that heritage and sustainability are not mutually exclusive and that well-designed renewable energy installations can be acceptable on or near listed buildings. The key principles:
Install on the least significant elevation — rear or hidden roof slopes are preferable to principal street-facing elevations
Use reversible installations where possible — panels must be removable without permanent damage to the historic fabric
Consider outbuildings, curtilage structures, or ground-mounted systems positioned away from the listed structure
Commission a Heritage Impact Assessment for Grade I and II* buildings to demonstrate awareness and justify harm versus benefit
Engage Historic England directly for Grade I and II* buildings — they are statutory consultees and their support is highly influential
The planning application process step by step
Where a planning application is required (or you wish to obtain a Lawful Development Certificate for certainty), the process in England follows these steps.
Confirm planning status of your site
Check whether your building is listed (NHLE database), whether your site is in a conservation area (council planning portal or local plan maps), whether any Article 4 Directions apply, and whether the site falls within any other designated area. This takes 30 minutes and prevents costly mistakes.
Pre-application advice (optional but recommended)
Submit a pre-application enquiry to the LPA for complex or sensitive sites. This gives you informal guidance from a planning officer before committing to a formal application. Costs £50–£600 depending on LPA and project scale; turnaround is typically 4–8 weeks. See the dedicated section below.
Prepare the application documents
A full planning application for commercial solar typically requires: a completed application form (via the Planning Portal at planningportal.planning.service.gov.uk); a site location plan at 1:1250 scale; a block plan at 1:500 or 1:200 showing the site layout; existing and proposed elevations and roof plans showing panel positions; a Design and Access Statement; and, for conservation area or heritage sites, a Heritage Impact Assessment or Conservation Area Appraisal response.
Submit via the Planning Portal
All planning applications in England must be submitted through the Planning Portal (planningportal.planning.service.gov.uk) with the appropriate fee. For most commercial solar applications, the fee is in the "Change of Use / Other Operations" category — currently £462 per 0.1 hectare of site area for "operations" applications (2026 fee schedule), subject to a maximum. Confirm current fees with your LPA or planning consultant.
Validation and public consultation
The LPA validates the application (checking all documents are present and fees paid) and commences a public consultation period — typically 21 days during which neighbours and statutory consultees can make representations. Statutory consultees for solar applications may include Historic England (listed buildings), Natural England (protected habitats or landscapes), and the Civil Aviation Authority (if near an airport).
Officer assessment and determination
A planning officer prepares a report assessing the application against local and national planning policies. Most commercial solar applications on industrial buildings are determined under delegated powers (by the officer rather than a planning committee) — they are typically non-contentious. The statutory determination period is 8 weeks for minor applications. If you have not received a decision within 8 weeks (and have not agreed an extension), you have the right to appeal on grounds of non-determination.
Pre-application advice — is it worth it?
Pre-application advice (often called "pre-app") is a paid informal consultation with your LPA's planning team before you submit a formal application. For factory solar projects in straightforward locations, pre-app is generally not necessary — the application is low-risk and the savings from pre-app do not outweigh the cost and delay.
However, pre-app is worth considering in the following circumstances:
When pre-app IS worth it
- - Conservation area or Article 2(3) land sites
- - Listed buildings (especially Grade I and II*)
- - Large ground-mounted systems over 1 MWp
- - Sites near scheduled monuments or World Heritage Sites
- - Any site where the planning outcome is genuinely uncertain
- - Where you need to invest significantly in design before application
When pre-app is probably not needed
- - Standard industrial building not in a designated area
- - Flat-roof ballasted system where PD applies
- - Where you are obtaining an LDC rather than full permission
- - Sites where similar solar applications have been approved nearby
- - Straightforward applications with clear PD status
Pre-app costs typically range from £50 (simple written advice from smaller LPAs) to £600 or more (meeting with planning officer at larger metropolitan councils). Turnaround varies from 4–8 weeks. The advice is informal and not binding on the LPA — a positive pre-app response does not guarantee approval — but it substantially reduces risk and allows you to design the installation with officer feedback before committing.
Typical timescales and costs
| Route | Typical Timescale | Approximate Cost | Notes |
|---|---|---|---|
| PD — no application needed | 0 weeks | £0 | Proceed straight to installation design and DNO application |
| Lawful Development Certificate | 6–10 weeks | £234 fee + £500–£1,500 agent | Recommended for high-value installations for legal certainty |
| Standard planning application (minor) | 8–16 weeks | £462+ fee + £1,500–£5,000 agent | Conservation area, Article 2(3) land, highway-facing panels |
| Listed Building Consent + planning | 12–24 weeks | Dual fees + £3,000–£10,000 agent + heritage consultant | Heritage Impact Assessment required; Historic England may be consultee |
| EIA development (large ground-mounted) | 16–52 weeks | £20,000–£100,000+ including EIA | Typically only for systems over 50kW ground-mounted or 1 hectare site area |
Common reasons for refusal and how to avoid them
Planning applications for factory solar are rarely refused — the policy context is strongly favourable and refusals are uncommon for standard industrial rooftop installations. Where refusals do occur, the most common grounds are:
Unacceptable impact on the character of a conservation area
AvoidableHow to avoid: ensure panels are not visible from the public highway. Use low-profile, dark-framed panels. Consider rear elevations. Provide a Conservation Area Appraisal response in your supporting statement demonstrating awareness of the area's character and how the installation respects it.
Harm to the special interest of a listed building
ManageableHow to avoid: commission a Heritage Impact Assessment. Propose reversible installation methods. Choose the least significant elevation. Engage with Historic England pre-application for Grade I and II* buildings. Consider outbuildings or ground-mounted alternatives.
Glare or visual intrusion affecting neighbours or roads
RareHow to avoid: modern panels with anti-reflective coatings rarely cause glare issues. If the site is adjacent to residential properties or near a road, request a glare assessment from your installer. Anti-reflective glass typically reduces reflectivity to less than 2%, well below levels that cause material harm.
Inadequate application documents
Easily avoidedHow to avoid: use a planning consultant or agent to prepare and submit the application. Missing documents cause invalid applications and delay — not refusals — but they extend timescales and cause frustration. A planning agent's fee of £1,500–£3,000 is a sound investment for any application on a sensitive or complex site.
How planning interacts with your DNO G99 application
For factory solar systems over 50kW, a G99 connection application to your Distribution Network Operator (DNO) is required before the system can connect to the grid. The planning and G99 processes are entirely separate and run in parallel — they are managed by different organisations (the LPA and the DNO respectively) and have no formal relationship with each other.
However, the practical interaction between the two is significant for project programming:
Planning and G99 Timeline Interaction
G99 application timescale: The DNO has 65 business days (approximately 13 weeks) to provide a connection offer following a G99 Stage 1 application. For larger systems requiring grid reinforcement, this can extend to 130 business days (26 weeks).
Best practice: Submit the G99 application at the same time as (or slightly before) the planning application. This way, both processes run in parallel and you receive your connection offer and planning consent at approximately the same time, minimising project delay.
Risk of sequential approach: If you wait for planning approval before submitting G99, you add 13–26 weeks to the project timeline. For a system requiring grid reinforcement, this could mean 6–12 months of additional delay.
Note on ENA G100: Systems exporting more than 17A per phase (approximately 12kW for a single-phase connection, or 36kW for three-phase) require G99 rather than the simpler G98 notification. All factory solar systems of meaningful commercial scale will fall under G99.
It is worth noting that DNO connection constraints in your area can be a more significant bottleneck than planning permission. In some parts of England — particularly in areas with high existing renewable generation — DNOs are imposing export limits (zero export or constrained export) on new commercial solar connections. This is a commercial and technical issue that must be investigated as early as possible in project development, ideally before you commit to a system design.
For a full walkthrough of the DNO application process and how to manage export constraints, see our guide to the Industrial Solar Installation Timeline UK.
Frequently Asked Questions
Do factories need planning permission for solar panels in the UK?
What is the maximum size of solar system allowed under Permitted Development for industrial buildings?
How long does planning permission for factory solar panels take?
Can a listed factory building get planning permission for solar panels?
Does a Lawful Development Certificate replace planning permission for factory solar?
Trusted Solar Installers Across the UK
We work with a network of MCS-certified regional installers. If you need a recommendation outside our coverage area, these are the firms we trust:
- ALPS Electrical — MCS-certified solar installer — Teesside & North East England
- Midland Solar — Commercial & industrial solar installer — West Midlands
- EC Eco Energy — UK-wide commercial solar & renewables installer
- YEERS — Solar panels & heat pumps — Yorkshire
- Carbon Legacy — Solar & green energy solutions — East Midlands
- Solent Solar — Commercial & residential solar installer — Hampshire & South Coast