Check the proposal and the property together. A similar project down the road does not establish what is allowed at your home.
Start with what you want to change
A new building, a substantial alteration or a change in how a building is used may need a planning application. Some smaller projects can use permitted development rights. These have conditions, so “small” is not a permission category on its own.
Write a short description of the work, with dimensions, photographs and a sketch. This gives the planning authority something specific to assess.
Check the property as well as the plans
Find out whether your home is listed, in a conservation area or affected by restrictions on earlier permissions. In England, the usual householder permitted development rights do not apply to flats and maisonettes, and an Article 4 direction can remove particular rights.
Ask about the exact work you propose. Permission for a neighbour’s extension may have been granted under different circumstances.
Get the right kind of confirmation
If the position is unclear, contact the planning authority before committing to the work. In England, a proposed lawful development certificate can formally confirm whether specified work would be lawful for planning purposes. It is a separate route from applying for permission on planning merits.
Also check building regulations and any other consents. A planning answer does not settle every approval your project might need.
Your next steps.
A quick checklist to keep your project moving.
- Describe the proposed work and its dimensions.
- Confirm whether the property is a house, flat or another type.
- Check previous permissions and property protections.
- Ask the planning authority which route applies.
- Check building regulations separately.
Sources & further reading
Checked 28 September 2026. Each source’s country is shown below.
- GOV.UK: when planning permission is needed ↗England
- mygov.scot: getting planning permission ↗Scotland
- nidirect: when to apply for planning permission ↗Northern Ireland
- Planning Portal: permitted development rights ↗England
- GOV.UK: lawful development certificates ↗England
- GOV.UK: building regulations approval ↗England and Wales