Which route, decided on evidence.
Prior approval is faster until it isn’t. Choosing the wrong route costs more than the application fee — it costs the months you spend on it before finding out.
Is this you?
What’s involved
Two routes, and they are not simply fast versus slow
| Route | What it puts in issue |
|---|---|
| Prior approval | A defined list of matters only — narrower, quicker, and it either fits or it doesn’t |
| Full permission | Everything, including the principle — but you argue the case on its merits |
The choice is not about speed. It’s about whether the building actually satisfies the qualifying criteria, and whether the defined matters can be answered on the evidence available.
Daylight is where prior approvals actually fail
The natural light requirement kills deep-floorplate conversions, and it fails schemes that look perfectly viable on plan. A former retail unit with a narrow frontage and thirty metres of depth has a real problem, and no layout ingenuity fixes a room with no window.
This is knowable at the start. It should be tested before the fee is paid, not discovered in week seven.
Dead space is where the value is
The commercially interesting question is rarely “can this shop become flats”. It’s what the building is doing with the space nobody is counting — the floor above the retail unit, the yard, the storage nobody has used since the last tenant.
Mixed schemes are harder to consent than single-use ones, and they’re usually worth more. Whether they’re worth the additional planning risk should be answered before the design work starts.
Proof
A prior approval secured — or a case where the advice was “this route won’t work, use the other one.”
Questions we’re asked
Is prior approval faster than a full application?
Usually, when the building qualifies. When it doesn’t, it’s a rejected application plus the time you spent on it, and you start again. The saving is real but it’s conditional.
Can I turn this shop into flats?
Often, subject to the qualifying criteria and the prior approval matters. Natural light to habitable rooms is the one that most commonly decides it, and it can be tested early.
Do I need permission at all?
Sometimes not. Movement within a use class often needs nothing, and permitted development may cover it — unless an Article 4 direction has removed the right locally. Worth a short check.
We already have an architect.
Good. Keep them. This is the question of which application to make, which is a different discipline from designing what goes in it.
Send us the building and the use you want.
We’ll tell you which route the evidence supports, what would defeat it, and whether it’s worth doing at all.
Discuss the building