Not every extension needs planning permission, and assuming it does — or assuming it doesn't — before actually checking is how projects either stall unnecessarily or start unlawfully. A householder planning application is the formal route used when a proposal genuinely falls outside permitted development, and understanding its stages helps set realistic expectations for timing.
The process is administered by the local planning authority covering the address, and while the broad stages are consistent nationally, response times and local emphasis vary between councils.
Establishing whether permitted development applies at all
Before an application is even drafted, the proposal is checked against permitted development limits — volume, height, proximity to boundaries, and whether the property has had those rights removed by an Article 4 direction or a planning condition on a previous approval. This step alone can remove the need for an application entirely, or confirm that one is unavoidable.
Properties in conservation areas or an Area of Outstanding Natural Beauty have reduced permitted development rights compared with the general default, which is a common reason a project that would be automatically allowed elsewhere in Kent needs an application here.
Preparing drawings to the authority's requirements
Each local planning authority publishes a validation checklist setting out what drawings and supporting documents an application needs before it will even be registered — typically existing and proposed plans and elevations, a location plan, and sometimes a design and access statement depending on the scale of work.
Drawings that don't meet the specific authority's checklist get rejected at validation stage before anyone has even assessed the merits of the scheme, which is a common and entirely avoidable source of delay.
Submission and the validation and consultation period
Once validated, the application is registered, neighbours are notified, and a public consultation period runs alongside the case officer's own assessment. Validation queries — a missing measurement, an unclear elevation — can come back at this stage and need responding to promptly to avoid the application clock resetting.
The statutory determination period for most householder applications is eight weeks from validation, though this can extend by agreement where the authority needs more time or where amendments are being negotiated.
Managing consultation comments and conditions
Neighbour objections and comments get considered by the case officer, though a comment alone doesn't determine the outcome — it's weighed against planning policy. Where an approval comes with conditions, some of these have to be formally discharged, often by submitting further details, before work can lawfully start.
Starting on site before a pre-commencement condition is discharged is a genuine risk, since it can render the permission invalid regardless of how minor the condition seemed.
Council-specific timing across Kent and East Sussex
Ashford, Maidstone, Tunbridge Wells, Tonbridge & Malling and Rother each administer the same national planning system but with their own case officer workloads, committee cycles and local policy emphasis, particularly around AONB land and conservation area character. Checking the specific authority's current validation requirements and any published guidance before submitting avoids delay caused by assuming one council's process matches another's.
Where a scheme sits in the High Weald or another AONB, expect closer scrutiny of materials, massing and impact on the landscape setting than a straightforward application on an unconstrained plot would receive.
Common questions
How long does a householder planning application take?+
The statutory target is eight weeks from validation, though straightforward applications sometimes come through faster and complex or contested ones can take longer, particularly if amendments are negotiated during the process.
Can I start groundworks while the application is being decided?+
No. Any work relying on the permission has to wait until it's granted, and any pre-commencement conditions attached to the approval have to be formally discharged before starting, not just noted and ignored.
What happens if my application is refused?+
You can amend and resubmit, often without a further fee within a set period, or appeal the decision. In practice, understanding the reason for refusal and revising the scheme to address it directly is usually quicker than an appeal.
Get help preparing your planning application
We work with designers who prepare drawings to each council's validation requirements, and can advise on permitted development before you commit to a full application.