Prior approval procedure: the clocks and the traps
Prior approval is not permission. It only works if the class conditions are met, and the 56-day deemed consent only runs from a valid application with the right fee.
The prior approval procedure looks like a light-touch planning application and behaves like a trap for anyone who treats it as one. It is not a grant of permission. It is a determination of whether the authority's approval is required for a short list of specified matters, on development that is already permitted by the General Permitted Development Order provided every limitation and condition in the relevant class is met. Get the class conditions wrong and the prior approval is worthless, because the development was never permitted development in the first place.
What prior approval is, and is not
Schedule 2 to the Town and Country Planning (General Permitted Development) (England) Order 2015 grants planning permission for defined classes of development. Some of those classes require the developer to apply to the authority first for a determination as to whether prior approval is required for particular matters.
The distinction matters in three ways.
The authority can only consider the matters the class lists, not the general planning merits. It cannot refuse because it dislikes the design unless external appearance is a listed matter. And a grant of prior approval does not cure a failure to meet the class conditions, so a building that turns out not to have been in the qualifying use for the required period was never permitted development, whatever the council wrote.
The classes landlords and investors use most sit in Part 3, covering changes of use, including Class MA from commercial, business and service use to dwellinghouses and Class Q from agricultural buildings to dwellinghouses. Part 1 Class A covers larger home extensions, Part 20 covers upward extensions and new dwellings on existing buildings, and Part 16 covers electronic communications.
The 56-day clock and how it is lost
For most prior approval classes the authority must give notice of its determination within 56 days of receiving the application. If it does not, the development may proceed in accordance with the details submitted.
Three things about that clock catch people out.
It runs from receipt of a valid application, and validity depends on the application containing everything the relevant paragraph of the Order requires and the correct fee having been paid. An incomplete submission does not start the clock, and authorities do say so months later.
It is 56 days, not eight weeks from validation, and it includes weekends and bank holidays.
And development must not begin before the authority notifies its determination or the 56 days expire, whichever is earlier. Starting early forfeits the protection entirely.
Validity: the trap that kills deemed consent
Each class sets out exactly what the application must contain. A written description of the proposed development, a plan indicating the site, the developer's contact address, and whatever assessments the class specifies.
Where a class requires a report dealing with a particular matter, its absence makes the application invalid rather than merely incomplete. Class MA requires the authority to consider transport and highways impacts, contamination risks, flooding risks, impacts of noise from commercial premises on the intended occupiers, and the provision of adequate natural light in all habitable rooms, among others. If a matter is listed, submit the evidence on it.
So the practical rule is to over-document. A Contaminated Land Assessment as a Phase 1 desk study, a Flood Risk Assessment where the site is in Flood Zone 2 or 3 or above one hectare, and a Noise Impact Assessment where the building adjoins commercial premises are not optional extras on a Class MA application. They are the evidence on the listed matters, and without them the council can either refuse or treat the application as invalid.
Natural light is the matter that most often defeats an office conversion. Deep floorplates with a single aspect will not provide adequate light to habitable rooms, and no amount of layout ingenuity fixes a windowless bedroom.
The matters the council can consider
Each class has its own list. Across the commonly used classes the recurring matters are transport and highways, contamination, flooding, noise from nearby commercial uses, the external appearance of the building, the impact on the amenity of adjoining premises, the provision of natural light, the effect on a conservation area or listed building, and, for taller residential schemes, fire safety.
Anything outside the list is irrelevant. An objection about loss of employment floorspace on a Class MA application, or about the principle of residential use, does not engage a matter the authority can consider, though it can engage a matter such as noise if it is expressed in those terms.
That constraint runs both ways. It is why prior approval routes are attractive, and why the authority will look hard at whether the class conditions are met, because that is the only place its discretion lives.
Conditions and completion deadlines
Prior approval grants are subject to the conditions in the class itself, and the authority can impose conditions on the matters it considered.
Several classes require the development to be completed within a period, commonly three years from the date of prior approval. A conversion that stalls can therefore lose the benefit of the class entirely, which is a real risk on a scheme funded on a bridge.
Some classes also restrict what happens afterwards. Permitted development rights for subsequent extensions are often removed, and a dwelling created under Part 3 may not benefit from the householder rights an ordinary house enjoys.
Article 4 and the other disqualifiers
An Article 4 direction removes permitted development rights in a defined area, and directions are common in conservation areas, in city centres for commercial to residential conversions, and in university towns for changes from Class C3 to Class C4.
Check for one before you do anything else, on the council's own website and on the planning constraints layer of its map. A direction can be made after you buy and before you apply.
The other disqualifiers are the class conditions themselves. Listed buildings, scheduled monuments, sites within safety hazard areas or military explosives storage areas, and land within a site of special scientific interest are excluded from many classes. Article 2(3) land, which includes conservation areas, National Parks and National Landscapes, restricts several householder rights and is defined in the Order.
A working checklist before you submit
- Confirm the class, and read its conditions and limitations in the current text of the Order rather than a summary.
- Check for an Article 4 direction and for any excluded designation on the site.
- Evidence the qualifying use and the qualifying period with documents, not assertions.
- Prepare a report on every listed matter, even where you expect no issue.
- Pay the correct fee and confirm in writing the date the authority treats the application as received.
- Diary day 56 and do not start before it.
- Note the completion deadline in the class and build it into the funding.
If prior approval is refused, there is a right of appeal to the Planning Inspectorate, and the appeal is decided on the listed matters. A refusal that strays outside them is worth appealing on that ground alone.
This is general guidance rather than legal advice. The classes are amended frequently, so check the current text of the Order with your local planning authority or a qualified professional before relying on this.
Enter your postcode on PlanScope to see which reports a prior approval application 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.
Frequently asked questions
What happens if the council misses the 56 days?
For most prior approval classes the development may then proceed in accordance with the details submitted. The protection only applies where the application was valid, meaning it contained everything the relevant paragraph of the Order requires and the correct fee was paid, and where development did not begin before the period expired.
Does 56 days mean eight weeks from validation?
No. It is 56 calendar days from receipt of a valid application, including weekends and bank holidays, and it does not run from a validation date the council assigns later. Confirm in writing the date the authority treats the application as received, and diary day 56 from that.
Can the council refuse prior approval because it dislikes the scheme?
Only on the matters the class lists, which vary by class but commonly include transport, contamination, flooding, noise, external appearance, natural light and impacts on amenity. Objections about the principle of the use or loss of employment floorspace do not engage a matter the authority can consider.
Does prior approval fix a failure to meet the class conditions?
No. If the building was not in the qualifying use for the required period, or the site is excluded by a designation, the development was never permitted development and the prior approval does not cure that. Evidence the qualifying use with documents before applying, not with assertions.
Is there a deadline to complete the development?
Several classes require completion within a set period, commonly three years from the date of prior approval, and a stalled conversion can lose the benefit of the class entirely. Check the class text and build the deadline into the funding, particularly on schemes financed with short-term lending.
Sources and further reading
This article is general guidance about the planning system in England and, where stated, the rest of the UK. It is not legal or professional advice. Check your local planning authority’s validation requirements and take professional advice for your specific site.