Planning Permission Guide 2026

Most single storey rear extensions do NOT require planning permission if they meet Permitted Development limits: 3 meters depth for terraced/semi-detached, 4 meters for detached houses. Extensions must be maximum 4m eaves height, 2.5m if within 2m of boundary, and not cover more than 50% of garden. The Extended Permitted Development scheme allows 6m/8m with Prior Approval (neighbor consultation). Flats and properties in Conservation Areas/Article 4 directions always need planning permission.

Planning permission fees in England for 2026 are: £258 for householder applications (extensions/alterations to single dwellings), £624 for new dwelling house, £120 for Prior Approval (larger extensions), £129 for Lawful Development Certificate. Add £70 Planning Portal service charge for online applications. Additional costs include planning drawings (£500-£1,500), pre-application advice (£60-£200), and planning consultants if needed (£1,000-£3,000+). Total cost typically £800-£2,500 for standard householder application.

Standard planning permission decision timescales are 8 weeks for householder applications and most full planning applications. Major developments have 13-week determination periods. Prior Approval applications are decided within 6 weeks. These are target timescales—delays can occur if additional information is requested or applications are referred to Planning Committee. Pre-application discussions add 4-6 weeks. Planning permission, once granted, typically lasts 3 years before development must commence.

Planning permission and Building Regulations are completely separate. Planning Permission (from Local Planning Authority) controls WHAT you can build—size, position, external appearance, impact on neighbors. Building Regulations (from Building Control) control HOW you build—structural safety, fire safety, insulation, drainage, ventilation. Most projects need BOTH approvals with separate applications and fees. Planning focuses on "does it fit?"; Building Regulations ensure "is it safe?". Even permitted development (no planning needed) always requires Building Regulations approval.

NO—you must wait for planning permission to be GRANTED before starting any work. Building before approval is "unauthorized development" and the council can issue an Enforcement Notice requiring demolition and restoration at your expense. There is no right to continue if permission is later granted. If exceptionally urgent, you can apply for retrospective planning permission AFTER building (same £258 fee) but councils often refuse retrospective applications and enforcement action is likely. Always wait for the decision notice before commencing.

Most loft conversions are Permitted Development and DON'T need planning permission if they meet criteria: volume allowance of 40m³ (terraced) or 50m³ (detached/semi), no extension beyond existing roof slope facing highway, no balconies/verandas, materials match existing, side windows obscure-glazed. Rear dormer windows are usually acceptable. However, flats, Conservation Areas, National Parks, Listed Buildings, and Article 4 areas require planning permission. You ALWAYS need Building Regulations approval for loft conversions regardless of planning status. Party Wall Agreement may also be required.

Neighbor objections are "material considerations" that planning officers must consider, but they don't automatically mean refusal. The weight given to objections depends on whether concerns relate to valid planning matters (overlooking, overshadowing, design, parking) rather than personal issues (property values, private disputes, loss of view). Multiple objections carry more weight. Planning officers assess objections against planning policies. If objections are significant, applications may go to Planning Committee for decision. You can address concerns by revising the proposal or submitting additional information.

Conservation Areas have STRICTER controls and significantly reduced Permitted Development rights. You'll need planning permission for: any extension to the side, enlargement to roof, cladding, satellite dishes on chimneys/front elevations, demolition of buildings/walls. Rear extensions may still be permitted development but with tighter restrictions. You must give 6 weeks notice before ANY tree work. External alterations require more careful design and materials must be sympathetic to the area's character. Always check with your Local Planning Authority before starting work in a Conservation Area.

YES—you have the right to appeal to the Planning Inspectorate within 12 weeks of refusal (householder) or 6 months (other applications). Appeals are FREE to submit. However, only 33% of householder appeals succeed. The Inspector reviews the application afresh and makes an independent decision. You can submit new evidence and revised drawings. Written representation appeals take 16-20 weeks. Alternatively, you can submit a revised application addressing refusal reasons within 12 months (often FREE if first application refused). Consider professional planning consultant advice before appealing.

Check your Permitted Development (PD) rights by: 1) Reviewing original planning permission for your house—look for conditions removing PD rights (common on new estates post-2000); 2) Contact your Local Planning Authority and ask if PD rights are restricted; 3) Check if in Conservation Area, National Park, AONB, Listed Building (restricted PD); 4) Apply for a Lawful Development Certificate (£129) for formal confirmation; 5) Use our Planning Permission Calculator. Flats and maisonettes have very limited PD rights. If uncertain, always seek confirmation before building.