Do you actually need planning permission?
Before applying, confirm that your project requires planning permission. Many common works — including most single-storey rear extensions and loft conversions — fall under Permitted Development rights and do not require a formal application. Check the Planning Portal (planningportal.co.uk) or consult your local planning authority for pre-application advice (usually £50–£200).
The application process
Most householder planning applications are submitted through the Planning Portal. You will need: site location plan (available from the planning portal for £3–£20), existing and proposed floor plans and elevations (produced by an architect or architectural technician), completed application form, and the application fee (£258 for a householder application in England). For applications involving listed buildings or conservation areas, additional documentation is required.
How long does planning permission take?
The statutory target for householder applications is 8 weeks. In practice, many councils take 10–13 weeks, particularly in busy planning departments. Pre-application discussions with the planning officer can significantly increase your chances of approval first time — a refusal and reapplication adds months to your project timeline.
What affects approval chances?
Planning decisions are based on the Local Development Plan and National Planning Policy Framework. For residential extensions, the key considerations are: impact on neighbouring amenity (overlooking, loss of light), bulk and massing, materials and design quality, and compliance with any local design guides. Consulting a neighbour before submitting is good practice and can prevent objections.