FAQ
Questions about ExtensionPlanner
Quick answers on what this tool can do, what it cannot do, and how permitted development fits into the results.
What does ExtensionPlanner do?
It checks a postcode in England against planning constraints and shows a plain-English planning risk report with a verdict, mapped constraints, and nearby planning activity context.
Can this tool tell me if my extension is definitely permitted development?
No. It gives an early risk signal, not a legal decision. For binding certainty, apply for a Lawful Development Certificate through your council.
What is permitted development?
Permitted development rights are national rules that allow some building works without full planning permission. These rights can be limited by factors like conservation areas, listed buildings, Article 4 directions, and local constraints.
Do I still need planning permission?
Maybe. If the report shows significant constraints, planning permission or specialist advice is more likely. If constraints are low, some works may be possible under permitted development, subject to full rule checks.
Does ExtensionPlanner replace an architect or planning consultant?
No. It helps you understand early planning risk and prepares you for the next conversation with a planner, architect, or your Local Planning Authority.
Is my data saved when I run a check?
No sign-up is required for a standard check and this page does not store your lookup as a user account record.