Prior approval: the halfway house before permission

Prior approval is a procedure that sits between permitted development and a planning application. The General Permitted Development Order has already granted permission for the development, so the principle is settled. What the council gets to decide is whether it approves the details of a short, fixed list of matters, such as transport, flooding, contamination or external appearance. Prior approval planning applications therefore succeed or fail on evidence about those specific matters, and nothing else is a lawful reason for refusal.

What prior approval actually is

The Order grants the permission. A condition attached to that grant says the developer must apply to the local planning authority for a determination as to whether its prior approval will be required for certain matters, and must not begin until the answer arrives or the period expires.

Two consequences follow, and they are the reason the procedure exists at all.

The council cannot refuse because it dislikes the principle. If a barn qualifies under Class Q, the fact that the officer would refuse a planning application for a house in that field is irrelevant. The permission is already granted by Parliament.

But the council is not powerless either. Paragraph W of Part 3 requires the authority, when considering a prior approval application, to have regard to the National Planning Policy Framework so far as it is relevant to the subject matter of the prior approval, as if the application were a planning application. So policy comes in through the listed matters, not around them.

The classes that use it

Prior approval is scattered across Schedule 2 and the details differ class by class. These are the ones a landlord, developer or homeowner meets most often.

Always read the class itself rather than a summary table, including this one. Each class carries its own qualifying conditions, its own exclusions on article 2(3) land and its own list of matters, and the classes have been amended repeatedly since 2015.

What the council may and may not consider

The listed matters are the boundary. If a class lists transport and highways impacts, contamination risks and flooding risks, then the officer cannot refuse because the units are small, because a neighbour objects to the principle, or because the local plan protects employment land.

That boundary cuts both ways. Where a class does list design and external appearance, as Class Q and Part 20 do, the officer has a genuine design judgement to make and can require changes to materials, fenestration and roof form. Applicants who treat those classes as a formality get a nasty surprise.

There is also a set of things that sit entirely outside the procedure. Building Regulations approval is separate and always required. Listed building consent is separate, and most classes exclude listed buildings anyway. Highways works in the public highway need the highway authority's own agreement. Community infrastructure levy liability can arise on a permitted development conversion where new floorspace is created or where the existing building has not been in lawful use for long enough, so check how levy liability arises before assuming a prior approval route is free of charges.

The clock, the deemed consent and the notices

The period runs from the day after the authority receives a valid application, and validity is where most disputes start. If the fee is short, or a required plan or notice is missing, the council will say the clock never started.

The outcomes at the end of the period are:

1. The authority notifies you that prior approval is not required. You may build, subject to the Order's conditions.
2. The authority grants prior approval, possibly with conditions. You may build in accordance with it.
3. The authority refuses prior approval. You may appeal.
4. The period expires with no decision notified. The development may proceed as described in the application, subject to the Order's conditions.

The fourth outcome is real and it is why paperwork discipline pays. Keep the submission receipt, the validation email and a dated record of what was submitted. If you intend to rely on expiry, write to the authority on the day after the period ends stating that you are proceeding on that basis and enclosing the approved description and plans.

Several classes also require site notices, neighbour notification or a notice to the owner where you are not the freeholder. Paragraph W sets out the publicity requirements for Part 3, and the larger householder extension route under Part 1 has its own neighbour consultation scheme with a 21-day objection window. Missing a notice invalidates the application.

Illustrative example

An illustrative case: an owner applies under the larger home extension route for a 5 m single-storey rear extension on a detached house. Two neighbours object within the 21 days, so the council must consider the impact on the amenity of adjoining premises. The officer looks at the depth relative to the neighbour's rear elevation, the height at the boundary and the effect on the neighbour's kitchen window, then approves subject to no conditions. Had nobody objected, the council would have issued a notice that prior approval was not required without assessing amenity at all. Same extension, different route through the process.

Why prior approval applications get refused

The refusals fall into a small number of patterns, and almost all of them are avoidable.

The building does not qualify. Wrong use history, wrong date, wrong floorspace, listed, or on excluded land. Check the qualifying conditions before you check anything else.

The submission is incomplete. Every class specifies the plans and information required, usually including a site plan, floor plans, elevations and a statement addressing each matter. A missing contamination assessment on a former industrial building is the classic.

An Article 4 direction removes the right. Directions are mapped by councils and increasingly published as open data, and a direction in force defeats the class outright.

The matters are answered thinly. A single paragraph saying flooding is not an issue, on a site partly in Flood Zone 2, invites a refusal that would have been avoidable with a flood risk assessment. Scoping the technical work against the full list of report types early is quicker than reacting to an officer's request on day 40.

And intensification catches people out where the prior approval route changes the level of activity rather than the building. Where a change of use is already happening on the ground before the application, the council may take the view that the relevant use has changed, which is a different problem covered by the rules on intensification.

Appeals and the cost of getting the class wrong

A refusal of prior approval carries a right of appeal to the Planning Inspectorate. So does a refusal to accept that a class applies. Appeals are decided on the same listed matters, so the appeal statement should be structured matter by matter with the evidence attached, not written as a general policy argument.

Where the class plainly does not apply, appealing is usually the wrong move. A full planning application puts the principle in play and lets you argue policy support, neighbour benefit and design quality, none of which the prior approval route allows you to raise. It costs more and takes longer, and on a marginal building it is often the faster route to a buildable consent.

If you want certainty before spending, a lawful development certificate for proposed use or development is the formal way to confirm that a class applies at all. That is a different application from prior approval, and on contested Class Q and Class MA buildings it is worth doing first.

This is general guidance, not legal advice; check the position with your local planning authority or a qualified professional before relying on it.

Enter your postcode on PlanScope to see which supporting documents your prior approval submission is likely to need.

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