Class A Part 14 GPDO 2015 — UK farm solar planning

The Town and Country Planning (General Permitted Development) (England) Order 2015 — commonly referred to as GPDO 2015 or the GPDO — establishes the Permitted Development framework for UK planning law. Class A Part 14 specifically covers solar PV installations on the roofs of agricultural buildings, removing the need for full planning permission in most cases.

What Class A Part 14 covers

The specific text of Class A Part 14 GPDO 2015 permits solar PV installation on the roofs of agricultural buildings subject to size and height limits. The headline permissions:

Rooftop installations on agricultural buildings: Permitted, no planning required, subject to: (i) the panels don’t protrude above the ridge of the roof; (ii) the panels don’t project more than 200mm from the roof slope (modern racking systems comply); (iii) the building is genuinely agricultural in use (not residential conversion, not retail-focus farm shop, not pure equestrian leisure).

Ground-mounted installations within agricultural curtilage: Permitted, no planning required, subject to: (i) total area of all ground-mount on the holding doesn’t exceed 9m × 9m × 4m height; (ii) installation is more than 5 metres from any boundary; (iii) panels are removed within 25 years.

These cover the vast majority of UK farm-building rooftop installations and most small ground-mount projects.

What Class A Part 14 doesn’t cover

Situations that need full planning permission rather than Permitted Development:

1. Listed buildings. Any rooftop PV on a listed building requires Listed Building Consent. Many UK farms have listed agricultural buildings — particularly listed barns, dairy parlours, threshing barns, granaries. Listed Building Consent timelines run 8-14 weeks and require conservation officer site visits.

2. National Parks and AONBs. Permitted Development still applies in principle, but local authorities can issue Article 4 directions removing the PD right for specific landscape features. Cotswolds AONB, South Downs National Park, Lake District National Park, and Snowdonia National Park have different practical positions. Check with the planning authority before assuming PD applies.

3. Conservation Areas. Permitted Development applies but the council may consult on visual impact. Conservation officers often have soft views on agricultural-building PV but engage on specifics like panel colour and mounting profile.

4. Ground-mount above 9m × 9m × 4m. Full planning required. For installations above 1 MW, Environmental Impact Assessment also required.

5. Buildings not in agricultural use. Barn conversions to dwellings, farm shops with significant retail focus, equestrian centres operating as pure leisure (not agricultural), former farm buildings in commercial use (offices, light industrial). These need full planning permission as commercial PV.

6. Curtilage of listed farmhouses. If PV is on a building within the curtilage of a listed farmhouse, Listed Building Consent may be required even if the agricultural building itself isn’t listed.

How to confirm Permitted Development applies

The practical sequence for any farm PV project:

1. Establish building use. Is the building genuinely agricultural? Check the rating record, planning history, and current use.

2. Check for listing. Search the Historic England National Heritage List for England, Cadw for Wales, Historic Environment Scotland for Scotland.

3. Check for designated landscape. Confirm whether the building is within an AONB, National Park, Conservation Area, World Heritage Site, or similar.

4. Check for Article 4 directions. Query the local planning authority for any current Article 4 directions covering the building.

5. Confirm size and orientation. Ridge height, panel projection from roof slope, total ground-mount area.

If all five confirm Permitted Development applies, the install can proceed without planning permission. We handle this assessment for every project as part of the feasibility stage — typically a 1-2 day desk exercise.

Pre-application advice

For borderline cases (listed building near agricultural building, AONB location, large ground-mount), pre-application advice from the planning authority is worth the £200-£500 fee and 4-6 week wait. The pre-app response gives a clear position the council can be held to during a subsequent full application.

Devolved differences

Wales has its own General Permitted Development Order (Town and Country Planning (General Permitted Development) (Wales) Order 1995 as amended) — similar to England but with subtle differences.

Scotland has the Town and Country Planning (General Permitted Development) (Scotland) Order 1992 as amended — slightly more generous for agricultural PV.

Northern Ireland has the Planning (General Permitted Development) Order (Northern Ireland) 2015.

Cross-check the right framework for the building’s location.

Common pitfalls

Things we see go wrong on farm PV planning:

1. Treating a building converted to residential as still agricultural — it isn’t; PV would need full planning permission as domestic PV.

2. Assuming PD applies on a listed farm building — Listed Building Consent is required regardless.

3. Underestimating Article 4 in AONBs — always check the specific landscape authority’s position.

4. Going ahead without checking conservation officer’s view on visual impact — typically resolved with minor design changes if engaged early.

5. Building exceeds the 200mm panel projection limit — uncommon with modern racking but possible on older corrugated profiles.

We handle the planning workstream on every project as part of our standard scope, including pre-application engagement, Listed Building Consent submission where required, and conservation officer liaison. Most farm-building rooftop installs proceed without any planning involvement — but knowing when planning is needed (and getting started early) avoids costly delays.