Planning Permission in London: A Complete Guide for Homeowners

Planning permission is required for development — and development is defined broadly to include most significant building work, change of use, and subdivision. For residential projects in London, planning permission is required when the works exceed Permitted Development rights (or when Permitted Development rights have been removed). Common residential projects that need planning permission in London: extensions larger than the Permitted Development size limits; extensions in conservation areas or subject to Article 4 directions; all extensions and alterations to flats and maisonettes (which have no PD rights); loft conversions involving front dormers or other works exceeding PD limits; two-storey extensions; outbuildings in conservation areas or over PD limits; change of use (converting an office to a dwelling, or splitting a house into flats); and any works to a listed building affecting its character (which require Listed Building Consent). London's dense conservation area coverage means that planning permission is required for a much higher proportion of residential works in London than in the rest of England.

Most planning applications in London are submitted through the Planning Portal (planningportal.co.uk) — the national online system for planning applications. The process: Choose the correct application type (Householder Planning Application for most residential extensions; Full Planning Application for changes of use or works to flats; Listed Building Consent for listed building works; Certificate of Lawfulness for PD confirmation). Prepare the required documents: architectural drawings (existing and proposed plans, elevations, sections, site location plan, block plan); a design and access statement; any specialist reports required (heritage impact assessment, transport statement, daylight/sunlight assessment depending on the specific project and borough). Pay the application fee: currently £258 for a householder planning application in England. Submit via the Planning Portal. The application is then validated by the council (1-2 weeks for straightforward applications), assigned to a planning officer, and put out for consultation. The statutory consultation period is 21 days for most applications. The target decision period is 8 weeks for householder applications (13 weeks for more complex applications). In practice, London councils often take 10-14 weeks for householder applications.

London's planning system operates at two levels: national policy (the National Planning Policy Framework) and London-specific policy. The Mayor of London's London Plan sets strategic policies for development across the capital — covering housing, design quality, density, transport, sustainability, and many other topics. Each of London's 32 boroughs (plus the City of London) also has its own Local Plan, which sets borough-specific policies for development. When assessing a planning application, a planning officer will assess the proposal against: national planning policy; the London Plan; and the relevant borough Local Plan and any supplementary planning documents (such as design guides, heritage guides, or residential design standards). For any significant London residential project, it is worth reviewing the relevant borough's residential design standards and householder extensions SPD (Supplementary Planning Document) before finalising the design — each borough has its own specific guidance on acceptable extension sizes, materials, and design approaches.

Pre-application advice is a service offered by most London boroughs that allows you to discuss a proposed development informally with a planning officer before submitting a formal application. It is particularly valuable for: complex or sensitive sites (conservation areas, listed buildings, sites with multiple constraints); large or unusual proposals where policy interpretation is uncertain; developments requiring specialist technical information; and projects where you want to understand the planning officer's likely view before investing in full architectural and technical work. Pre-application advice fees vary by borough: typically £200-£600 for a householder residential enquiry. This fee is often very good value — a pre-application meeting that identifies a fundamental policy objection to your proposal (or confirms it will be supported) can save thousands of pounds in design and application costs. Pre-application responses are material planning considerations but are not binding — the formal application is assessed on its own merits at the time of submission.

If your planning application is refused, the decision notice will set out the reasons for refusal. Options after a refusal: amend and resubmit (if the refusal reasons are addressable by design changes, a free resubmission can be made within 12 months of the original decision — amended applications are given the same 8-week target); appeal to the Planning Inspectorate (you have 12 weeks from the refusal date to submit an appeal; the Planning Inspectorate is an independent body that assesses the appeal on its planning merits; approximately 35-40% of householder appeals are allowed); apply for Enforcement Action costs recovery (if the council has behaved unreasonably, costs can be claimed against them in the appeal process). For most householder applications in London, an amended resubmission addressing the specific refusal reasons is the most time-effective route after a refusal. If the refusal is based on a fundamental policy objection (such as the scale of the proposed development being unacceptable in principle), a redesign is necessary before resubmission.