Cornwall
Planning & Building Contacts

Key planning considerations across Cornwall:
St Ives: Primary residence requirement (introduced 2016 via Neighbourhood Plan) - new open market dwellings must be used as a primary residence; holiday lets require planning permission in large parts of the town. Article 4 Direction withdraws some permitted development rights.
Cornish Mining WHS: The Cornwall and West Devon Mining Landscape UNESCO WHS covers former tin and copper mining areas across west Cornwall - engine houses, stacks and adits are scheduled monuments; development near or within the WHS requires careful heritage assessment.
Cornwall National Landscape (AONB): Covers much of coastal and moorland Cornwall - development must demonstrate exceptional circumstances.
Bodmin Moor National Landscape: Upland moorland area - highly protected; Scheduled Monuments throughout.
China clay: St Austell area has extensive china clay workings and tips (Wheal Martyn). China clay operations are subject to minerals planning policy; residential development near tips requires geotechnical assessment.
Second homes: Cornwall has among the highest second-home rates in England - planning policies increasingly restrict new open market housing for holiday/second-home use across popular coastal areas beyond St Ives.

The Council of the Isles of Scilly is one of England's most unusual local authorities - a unique council of the Isles sui generis, covering 5 inhabited islands with a combined population of around 2,200. The entire archipelago is an Area of Outstanding Natural Beauty and a Special Area of Conservation. Development is highly restricted, materials must be sympathetic to island vernacular, and supply chain logistics (everything arrives by boat or helicopter) must factor into any construction programme. There is no mains gas or mains electricity grid - power is generated locally. Pre-application advice is essential.

Radon protective measures: Much of Cornwall is in a high-radon area. Building Regulations Approved Document C requires radon protective measures for new dwellings in Radon Affected Areas. Cornwall Council building control surveyors are experienced with radon membrane and underfloor ventilation requirements. Confirm radon designation for the specific site with UKHSA radon maps at the application stage.

Cornwall and West Devon Mining Landscape UNESCO WHS (inscribed 2006): Covers 10 historic mining areas across west Cornwall including Camborne-Redruth, St Just, Gwennap, Hayle and Tamar Valley (crossing into Devon). Engine houses, count houses, mine workings and associated industrial settlements are Scheduled Monuments. Development within the WHS or its buffer zone requires pre-application consultation with Historic England. Cornwall's prehistoric landscape - standing stones, fogous, cliff castles - is among the richest in Britain. Truro Cathedral (Grade I); Pendennis Castle (Grade I); St Michael's Mount (Grade I).

The Cornwall HER contains records of over 60,000 heritage assets. Pre-application HER search is strongly recommended. Mine shafts and adits are widespread across west and mid-Cornwall - even outside the formally designated WHS areas, former mining ground presents structural risks. The Coal Authority is not relevant here; Cornwall's mineral extraction legacy is managed through Cornwall Council and Historic England.

The WHS Management Plan sets out policies for the protection and presentation of the Outstanding Universal Value. Development proposals within or affecting the setting of the WHS should be checked against the Management Plan and may require a World Heritage Impact Assessment in addition to standard heritage statements.

Key flood risk and environmental issues in Cornwall:
Coastal erosion: Cornwall's coastline is subject to active erosion, particularly on softer cliff types - Coastal Change Management Areas apply in many locations; development at risk of erosion within 100 years will face resistance unless a temporary or relocatable approach is proposed.
Estuaries: Fal Estuary (Special Area of Conservation - one of the deepest natural harbours in Europe), Camel Estuary, Fowey Estuary, Helford River - all European protected habitats requiring Habitats Regulations Assessment for development affecting their integrity.
Mine water drainage: Legacy tin and copper mining has left acidic and metal-rich mine drainage affecting some watercourses in west Cornwall. Phase 1 contamination surveys are standard practice for development on former mining land.
Hayle Estuary: SPA/Ramsar site at the head of St Ives Bay - development in the Hayle regeneration area must satisfy Habitats Regulations Assessment requirements.

Cornwall Council is the LLFA for surface water flood risk. As the county is largely rural with steep-sided valleys (combes), surface water runoff can be rapid and intense. Sustainable Drainage Systems (SuDS) are required for major development; SuDS approval is handled by Cornwall Council as the SuDS Approving Body (SAB). Consult the Cornwall Surface Water Management Plan for strategic flood risk context.

Many rural Cornish properties rely on private water supplies (boreholes, springs) and private sewage treatment (septic tanks or package treatment plants). Cornwall has a significant number of listed buildings on private water - any conversion or extension will need to address private water quality. South West Water operates Wastewater Treatment Works throughout the county; capacity constraints in rapidly growing coastal towns (Newquay, St Ives, Falmouth) can affect development viability.

Cornwall is a peninsula at the end of the national electricity grid - grid connection costs and timescales can be significant for new development, particularly in west Cornwall and the Penwith peninsula. Cornwall has been a leader in renewable energy (wind, solar, tidal) but grid constraint has historically limited export. Engage NGED early for any development requiring new grid connections or significant additional load.

Important: The vast majority of Cornwall has no mains gas supply - oil, LPG, biomass and heat pumps are standard heating solutions. This applies to most rural areas, all of Penwith (Land's End peninsula), the Lizard peninsula, most of north Cornwall, and many coastal towns. New builds in Cornwall are among the best-placed in England to comply with Future Homes Standard requirements since heat pumps are already the norm, but the granite building stock can present retrofit challenges for older properties.

The A30 is the sole strategic road link into Cornwall - capacity and resilience is a critical planning consideration for all major development. Newquay Cornwall Airport safeguarding zones affect a swathe of mid-Cornwall - height of development and telecommunications masts must be checked. Tamar Bridge crossing (Plymouth-Saltash) is managed by the Tamar Bridge and Torpoint Ferry Joint Committee; tolls apply westbound.

Radon is a significant issue in Cornwall. Over 50% of Cornwall is classified as a Radon Affected Area with 1% or more of homes above the Action Level. Building Regulations require radon protective measures in these areas. Developers and building control should check the postcode-level radon map at ukradon.org for each site. Cornwall Council planning applications for new residential development in high-radon areas will typically include a radon condition requiring compliance with BS 8485.

The Duchy of Cornwall is one of the largest landowners in Cornwall, owning significant agricultural, residential and commercial property. Development proposals on Duchy land require Duchy consent in addition to planning permission. The Duchy has a strong interest in sustainable development and traditional building practices. Nansledan (Newquay) is a major Duchy-led urban extension based on traditional urban design principles.

Cornwall has exceptional biodiversity including greater horseshoe bats (population stronghold), basking sharks, cirl buntings, choughs (Cornwall's county bird), and extensive reef and seagrass habitats. Ecological surveys are frequently required for development outside settlement boundaries. Cornwall NatureScape mapping identifies key habitats and ecological networks that must be considered in development proposals.