Permitted development (PD) is a national grant of planning permission that allows certain works without a formal application. Planning permission requires submitting an application to your council, paying a fee, and waiting for a decision. PD is faster and free, but has strict size and design limits. Planning permission offers more flexibility but takes 8 weeks and costs £258.

Your project qualifies for PD if it meets specific criteria covering size, height, position, and materials. The limits vary by property type and location. Key factors include whether your house is detached or attached, whether you're in a conservation area, and whether your council has removed PD rights through an Article 4 direction. Projects exceeding any limit require planning permission instead.

You should apply for planning permission when your project exceeds PD limits, when you want more design flexibility than PD allows, when your property is in a conservation area or is listed, when PD rights have been removed, or when you're combining multiple elements that together fall outside PD scope. Wraparound extensions typically need permission because they combine side and rear elements.

PD is free, with no application fees. There's no 8-week waiting period for a council decision. Neighbours cannot object or block your project. You have certainty that you can build within the specified limits. The process is faster, so you can start work sooner. For straightforward projects within the limits, PD is usually the better route.

Planning permission lets you build larger than PD limits allow. You have more design flexibility with materials, roof forms, and positioning. Approval gives you documented permission that's easy to prove when selling. You can negotiate with officers to find an acceptable scheme. For ambitious projects, planning permission may be the only way to achieve what you want.

Yes. A Lawful Development Certificate (LDC) costs £129 and provides legal confirmation that your project falls under PD. The council assesses your plans against PD criteria and issues a certificate if compliant. While not mandatory, an LDC protects you if rules change, provides proof for future buyers, and avoids disputes about whether work was lawful.

If your project doesn't meet PD criteria, it's unauthorised development. Your council can take enforcement action requiring you to remove or alter the work, or apply for retrospective permission. When selling, solicitors will check compliance, and unauthorised work can delay or collapse sales. If in doubt, get a Lawful Development Certificate before starting.

No. Permitted development rules differ between England, Wales, Scotland, and Northern Ireland. England has the most generous PD rights for extensions. Wales has similar but not identical rules. Scotland uses a different system with its own limits. Northern Ireland has separate planning legislation. Always check the rules that apply to your specific location.

For standard PD projects, no. Your neighbours have no right to object because there's no application to comment on. However, under the Larger Home Extension scheme (for extensions beyond standard limits), neighbours are formally notified and can raise concerns. If they object, your council decides whether the larger extension can proceed.

If your project is close to PD limits, you have options. You could scale back slightly to stay safely within PD. You could apply for a Lawful Development Certificate to confirm compliance. Or you could apply for planning permission anyway to get documented approval and avoid uncertainty. For borderline cases, professional advice from an architect or planning consultant is often worthwhile.