Cornwall
England's most south-westerly county, a peninsula of dramatic coastline, moorland, and a rich Celtic heritage.
Planning Permission in Cornwall
Planning permission for a self-build home in Cornwall is obtained from Cornwall Council, the unitary authority for the entire peninsula. The council's planning and building pages provide comprehensive guidance on the application process, document requirements, fees and pre-application advice.
Cornwall's Local Plan Strategic Policies document, adopted in November 2016, is the primary planning policy framework for the county. Policy 1 (Presumption in Favour of Sustainable Development) sets the overall approach, while Policy 12 (Design) establishes the council's design quality expectations. Policy 12 requires development to demonstrate a high standard of design that is informed by local character and that contributes positively to the quality of the built environment. The council's Design Guide for Housing provides the detailed supplementary guidance that planners use to assess applications.
The Cornwall AONB is a material consideration for all planning applications within its boundaries, and the Cornwall AONB Management Plan sets out the strategic framework for development affecting the designated landscape. Self-build proposals within the AONB must address the potential impact on the AONB's special qualities in the design and access statement, and officers will assess proposals against the AONB management plan's development policy principles. Applications for major development within the AONB face a high test of justification under Paragraph 172 of the National Planning Policy Framework.
Community Infrastructure Levy in Cornwall is charged at rates set out in the council's CIL charging schedule. The schedule distinguishes between different zones and dwelling types. Self-builders who qualify for the self-build CIL exemption - intending to occupy the home as their principal residence for at least three years - can avoid CIL liability by submitting the exemption claim form before development commences. A completion declaration must be submitted within six months of first occupation. Cornwall Council's CIL team administers the exemption process and can confirm the applicable rate for any specific site.
Validation requirements for planning applications in Cornwall are set out in the council's validation checklist. Standard requirements include a completed application form, location and site plans, a design and access statement, and the statutory fee. Additional documents required depending on site circumstances include: a flood risk assessment for sites in or near Flood Zones 2 or 3; a heritage impact assessment for sites near listed buildings, scheduled monuments or within conservation areas; an ecological survey where protected species including choughs, cirl buntings or otters may be present; a contaminated land assessment for former industrial sites; and a landscape and visual impact assessment for sites in the AONB or open countryside.
The pre-application advice service operated by Cornwall Council is particularly valuable for self-builders given the county's complex planning environment. Officers can advise on design principles, heritage constraints, flood risk and ecological requirements before significant design costs are incurred. The service charges a fee depending on the scale and complexity of the scheme, and written advice is provided within a defined timescale.
Section 106 planning obligations are used in Cornwall to secure contributions toward affordable housing, open space and transport. Single self-build plots typically fall below the affordable housing threshold, but this should be confirmed with the council's planning obligations team during pre-application engagement. Heritage and ecological mitigation requirements are sometimes secured by planning condition rather than S106 obligation for smaller residential developments.
Cornwall's planning service also administers applications under the county's rural exception site policies, which allow affordable housing in rural locations that would not otherwise be acceptable for development. Self-builders seeking a rural plot should explore whether their preferred location might benefit from a rural exception site approach, particularly where there is a demonstrable local housing need.
Cornwall's Local Plan Strategic Policies document, adopted in November 2016, is the primary planning policy framework for the county. Policy 1 (Presumption in Favour of Sustainable Development) sets the overall approach, while Policy 12 (Design) establishes the council's design quality expectations. Policy 12 requires development to demonstrate a high standard of design that is informed by local character and that contributes positively to the quality of the built environment. The council's Design Guide for Housing provides the detailed supplementary guidance that planners use to assess applications.
The Cornwall AONB is a material consideration for all planning applications within its boundaries, and the Cornwall AONB Management Plan sets out the strategic framework for development affecting the designated landscape. Self-build proposals within the AONB must address the potential impact on the AONB's special qualities in the design and access statement, and officers will assess proposals against the AONB management plan's development policy principles. Applications for major development within the AONB face a high test of justification under Paragraph 172 of the National Planning Policy Framework.
Community Infrastructure Levy in Cornwall is charged at rates set out in the council's CIL charging schedule. The schedule distinguishes between different zones and dwelling types. Self-builders who qualify for the self-build CIL exemption - intending to occupy the home as their principal residence for at least three years - can avoid CIL liability by submitting the exemption claim form before development commences. A completion declaration must be submitted within six months of first occupation. Cornwall Council's CIL team administers the exemption process and can confirm the applicable rate for any specific site.
Validation requirements for planning applications in Cornwall are set out in the council's validation checklist. Standard requirements include a completed application form, location and site plans, a design and access statement, and the statutory fee. Additional documents required depending on site circumstances include: a flood risk assessment for sites in or near Flood Zones 2 or 3; a heritage impact assessment for sites near listed buildings, scheduled monuments or within conservation areas; an ecological survey where protected species including choughs, cirl buntings or otters may be present; a contaminated land assessment for former industrial sites; and a landscape and visual impact assessment for sites in the AONB or open countryside.
The pre-application advice service operated by Cornwall Council is particularly valuable for self-builders given the county's complex planning environment. Officers can advise on design principles, heritage constraints, flood risk and ecological requirements before significant design costs are incurred. The service charges a fee depending on the scale and complexity of the scheme, and written advice is provided within a defined timescale.
Section 106 planning obligations are used in Cornwall to secure contributions toward affordable housing, open space and transport. Single self-build plots typically fall below the affordable housing threshold, but this should be confirmed with the council's planning obligations team during pre-application engagement. Heritage and ecological mitigation requirements are sometimes secured by planning condition rather than S106 obligation for smaller residential developments.
Cornwall's planning service also administers applications under the county's rural exception site policies, which allow affordable housing in rural locations that would not otherwise be acceptable for development. Self-builders seeking a rural plot should explore whether their preferred location might benefit from a rural exception site approach, particularly where there is a demonstrable local housing need.
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