Planning Permission for Solar & Heat Pumps in Cornwall: Full Guide 2026

Permitted Development Rights: The Basics

Most solar panel and heat pump installations on residential properties in Cornwall fall under permitted development rights — meaning no planning permission is needed, provided the installation meets specific criteria. However, these rights can be restricted or removed in specific circumstances: conservation areas, listed buildings, and large installation sizes.

Solar Panels: Permitted Development Criteria

• Panels do not protrude more than 200mm above the roof plane
• Panels are not installed on a wall or roof slope facing a highway
• The property is not a listed building (requires listed building consent)

For standalone ground-mounted solar, permitted development allows systems up to 9m² within the curtilage of a dwelling. Larger arrays need full planning permission.

What this means in Cornwall specifically: the overwhelming majority of roof-mounted domestic solar installations across Cornwall proceed under permitted development with no planning application at all. Cornwall Council administers planning for the whole county (there are no separate district authorities), so the rules are applied consistently from Penzance to Bodmin. The two situations where Cornwall homeowners most often need to pause are (1) a property in one of the county's 140-plus conservation areas where the proposed panels face a highway, and (2) a listed building, where listed building consent is required regardless. If your roof faces away from the road, or your highway-facing slope is not the one being used, permitted development almost always applies. Read our dedicated solar panels in Cornwall page for local irradiance figures, costs and the full installation process, and our Cornwall solar planning guide for a deeper dive on conservation, AONB and listed-building cases.

Heat Pumps: Permitted Development Criteria

• Volume of the outdoor unit does not exceed 0.6m³
• Unit is not installed on a roof (wall or ground mounting only)
• Only one heat pump installed at the property
• Unit is at least 1 metre from the property boundary
• Not on a listed building or within a conservation area on a highway-facing wall
• Meets MCS planning standards for noise (typically 42dB at 1 metre)

Conservation Areas in Cornwall

Cornwall has over 140 conservation areas. Key areas in our service territory:

• Fowey: Extensive conservation area. Solar panels on highway-facing roofs require permission.
• Lostwithiel: Medieval town centre. Front elevation restrictions apply.
• Mevagissey: Working fishing village. Heat pumps on harbour-facing walls require permission.
• Charlestown: UNESCO World Heritage Site buffer zone. Pre-application advice strongly recommended.
• Truro city centre: Multiple conservation areas around the cathedral and historic streets.

See also: Solar Panels in Cornwall Conservation Areas.

Listed Buildings

Listed buildings require listed building consent for alterations that affect the character of the building — including solar panels and heat pump outdoor units. This is separate from planning permission and must be applied for even if the installation would otherwise be permitted development.

AONBs & National Landscape Designations

The Cornwall National Landscape (the AONB, renamed in 2023) is one of the largest in the country, covering around a third of the county across 12 separate sections — including much of the Roseland Peninsula, the coast between Mevagissey and Fowey, the north Atlantic coast, the Camel estuary, and the fringes of Bodmin Moor. Crucially for homeowners, AONB / National Landscape status does not remove permitted development rights for domestic solar panels or a single domestic heat pump. A roof-mounted array on a house inside the Cornwall National Landscape is treated the same as one outside it, provided the standard PD criteria are met (panels under 200mm proud of the roof, not on a highway-facing slope of a building in a conservation area, not a listed building).

Where the designation does bite is on the cases that already need a full planning application — ground-mounted arrays above 9m², larger or commercial installations, or any scheme on a property where PD rights have been removed by an Article 4 Direction. In those cases the landscape impact becomes a material consideration and sensitive siting (screening, low-glare panels, positioning away from public viewpoints) matters. A good rule of thumb for Cornwall: a standard roof install on a normal house in the National Landscape is almost always permitted development; anything ground-mounted or visually prominent is worth a pre-application check. Our solar panels in Cornwall service includes assessing exactly this for your property.

Pre-Application Advice

If uncertain, Cornwall Council's Planning Department offers a pre-application advice service for £66 (2026 fees), with a written response within 20 working days. CCS Heating & Renewables will advise you during your free survey whether your installation requires any planning application. Book a free survey and we'll assess your specific property's planning position as part of the visit.