Prior approval: what the council can actually refuse on

A council determining a prior approval application can only refuse on the matters the General Permitted Development Order lists for that class. Nothing else. Prior approval refusal grounds are closed, so an officer who dislikes the unit mix, wants affordable housing, or thinks the scheme conflicts with a local plan policy on employment land has no route to say so unless that subject appears in the list for the class you are using.

Investors lose money by forgetting this and treating the process as a softer planning application. It is not a softer anything. It is a different instrument.

Permission already exists

The permission is granted by the Order itself, made under section 59 of the Town and Country Planning Act 1990. What the prior approval process does is impose a condition on that grant: before you build, ask the local planning authority whether its approval is required for certain specified matters.

So the council is not deciding whether to permit the development. It is deciding whether the specified matters are acceptable, and if they are not, whether they can be made acceptable by condition. That framing changes how you write the submission. A Planning Statement for a prior approval should march through the matters in the order the Order lists them and stop, rather than arguing the general planning merits of the scheme.

For most Part 3 changes of use, the procedure sits in paragraph W of Schedule 2 Part 3, which sets the application requirements, the consultation, the time limit and the obligation on the authority to have regard to the National Planning Policy Framework so far as it relates to the subject matter of the prior approval.

The matters list is the council's whole remit

Each class has its own list. Class MA, for commercial to residential conversion, has matters covering transport impacts and highway safety, contamination, flooding, noise from commercial premises affecting future occupiers, the loss of a ground floor use in a conservation area, the effect of introducing housing into an area important for industry or storage and distribution, the provision of adequate natural light to all habitable rooms, and fire safety in taller buildings. Class Q for agricultural buildings has a different list including whether the location makes residential use impractical or undesirable, and design and external appearance.

Read the list for your class before you draw anything. Two consequences follow.

First, evidence goes where the matters are. If flooding is on the list, a Flood Risk Assessment proportionate to the flood zone answers it. If contamination is on the list, a desk study by a suitably qualified and experienced person is the starting point, and that is a report type where professional input is expected rather than optional. If noise from nearby commercial premises is on the list, a Noise Impact Assessment addressing internal noise levels for the intended occupiers is the answer.

Second, do not volunteer evidence on matters that are not listed. Submitting a daylight study for a class that does not include natural light hands the officer a document to find fault with, on a subject they cannot lawfully refuse on.

Information a council can and cannot require

Paragraph W lets the authority ask for the information reasonably necessary to determine the application, and councils sometimes stretch that. Requests for a design and access statement, a heritage appraisal on an unlisted building outside a conservation area, or an affordable housing statement are common and are usually outside the remit.

The practical response is not a fight. Write back, politely, setting out which matter in the class list the requested document relates to, and ask the officer to identify it. Where the request does relate to a listed matter, provide it quickly. Where it does not, say so in writing and note the date, because the clock does not stop while an authority asks for material it cannot require.

Councils can, and routinely do, consult neighbours and put up a site notice. Objections about matters outside the list still arrive. They cannot form the basis of a refusal.

When the determination period runs out

Most Part 3 prior approvals run to 56 days from the day the valid application is received. Larger householder extensions under Part 1 run to 42 days. If the authority does not notify you of its decision within the period, the development may proceed in accordance with the details submitted.

This deemed consent is real, and it is also narrower than people assume. It only covers the prior approval requirement. Every other limitation and condition in the class still applies, so a scheme that never qualified for the class in the first place gains nothing from silence. Before relying on the expiry, check three things: that the application was valid and the fee paid, that the date of receipt is the one you think it is, and that the class limitations are all met on the facts.

If you are going to rely on the deemed route, tell the council in writing that you consider the period expired on a stated date and that you intend to proceed. It costs nothing and it makes the record clear.

Conditions the Order imposes anyway

A prior approval is not a blank cheque. The class itself carries conditions, and those bind you whether or not the council mentions them.

Common examples across Part 3 classes are a time limit for completing the development, usually three years from the date of approval, restrictions on further changes of use afterwards, and requirements that the development be carried out in accordance with the details approved. Some classes restrict the resulting use to a particular class and remove permitted development rights that a normal dwelling would enjoy.

Breach those and you have unauthorised development, with the enforcement consequences that follow.

Appealing a refusal

A refusal of prior approval is appealable to the Planning Inspectorate under section 78 of the 1990 Act, on the same six-month footing as other appeals, and the appeal is decided against the same closed list of matters.

These appeals are often winnable, because the argument is narrow and technical. Where a council has refused on a ground outside the list, that is close to a self-inflicted wound, and an application for costs on the basis of unreasonable behaviour is worth considering. Where the refusal is on a listed matter, the appeal turns on evidence rather than policy debate, so the fix is usually a better report than a better argument.

Non-determination is different. Silence past the deadline is normally an advantage, not a grievance, so read the file before appealing.

Keeping the record for a future sale

Prior approval paperwork gets lost, and buyers' solicitors ask for it years later.

Keep the decision notice, the stamped drawings, the application form and the receipt, evidence of the date of receipt where deemed consent was relied on, and any documents proving the class conditions were met, for example the evidence of prior use or vacancy that the class required. Photographs dated during the works help. Where a class required works to be completed within three years, the completion date matters.

If the paperwork is already gone, a lawful development certificate for an existing use under section 191 of the 1990 Act is the way to regularise the record, supported by statutory declarations.

This is general guidance, not legal advice; check the position with your local planning authority or a qualified professional before relying on it, and remember that a lawful development certificate is the only formal way to confirm that works are lawful. Enter your postcode on PlanScope to see which reports a prior approval application on your site is likely to need. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.