Material change of use: the test councils apply

A material change of use is a change in the character of what a piece of land or a building is used for, judged as a matter of fact and degree. It is one of the two limbs of development in section 55 of the Town and Country Planning Act 1990, and it needs planning permission. The word doing the work is "material". Councils are not asking whether something about the use has changed. They are asking whether the planning consequences of the new use differ enough from the old one to matter.

The statutory starting point in section 55

Section 55(1) defines development as building, engineering, mining or other operations, or the making of any material change in the use of any buildings or other land. Operations and uses are treated differently, which is why fitting a new shopfront and switching from a shop to a hot food takeaway are assessed under separate limbs.

Section 55(2) then carves out things that are not development at all. Two matter for a business. Section 55(2)(f) says that a change from one use to another use within the same class of the Town and Country Planning (Use Classes) Order 1987 is not development. Section 55(2)(d) covers uses incidental to the enjoyment of a dwellinghouse within its curtilage.

Nothing in the Act tells you what "material" means. That has been left to the courts and to case officers, which is why the answer so often starts with a judgement rather than a rule.

Character of use, not the activity on any given day

The first question an officer asks is what the planning unit is. The usual approach follows Burdle v Secretary of State for the Environment (1972): normally the unit is the whole of a single occupier's holding, unless there are two or more physically separate and distinct areas occupied for substantially different purposes, in which case each is its own unit.

Get the unit wrong and the analysis collapses. A restaurant that starts doing deliveries from a rear kitchen has not created a separate planning unit if the kitchen serves the restaurant. Fence that kitchen off, give it a separate entrance and let it to a delivery operator, and you probably have.

The second question is the character of the use, taken over a period rather than on a Tuesday afternoon. Character covers who comes, when, how, in what numbers, what noise and smell the use produces, what servicing it needs and what it does to the street. A gym running two spin classes a week and a gym running classes from 6am to 10pm are the same use class. Whether they are the same use in character is a different question, and one that turns on evidence.

Ancillary use is the third concept. A use that is wholly subordinate to the main use needs no permission of its own. An office above a shop, used by the shop, is ancillary. Let that office separately and it becomes a primary use in its own right, and the change is material.

Movements inside Class E and why they are not development

The 2020 amendments to the Use Classes Order created Class E, Commercial, Business and Service, and it is wide. It takes in retail (E(a)), cafés and restaurants (E(b)), financial and professional services (E(c)), indoor sport and fitness (E(d)), medical and health services (E(e)), creches and day nurseries (E(f)) and offices, research and development and light industrial uses (E(g)).

Moving between any of those is not development, so no permission is needed and no application is made. A shop becoming a café, a café becoming a dentist, an office becoming a gym. All of those sit inside Class E and outside the planning system, subject to two caveats that catch people out.

The first caveat is conditions. If your permission or a predecessor's permission carries a condition restricting the use to a named purpose, that condition binds you regardless of Class E. Restrictive conditions on retail parks and mixed-use ground floors are common. Read the decision notice and its conditions before you rely on the class.

The second is Article 4 directions. A council can withdraw permitted development rights, and several have made directions covering the Class E to residential route under Class MA. A direction cannot stop movement within Class E itself, because that movement is not development, but it can stop the next step you were planning.

When a small shift becomes material

Three shifts turn up again and again in change of use decisions, and all three sit at the edge of Class E.

Hot food takeaway is the clearest. Since the 2020 amendments, a use for the sale of hot food principally for consumption off the premises is sui generis, outside Class E. So a café adding a serving hatch and a delivery-driver waiting area is moving towards a use that needs permission, and the council will look at the split between eat-in and takeaway trade, not at the menu.

Drinking establishments are also sui generis. A café with a licence that trades as a bar in the evenings is running a use the Order treats separately, and officers will look at seating, table service, food revenue share and closing times.

Intensification is the third and the hardest. More of the same use is not automatically a material change, but it can be when the character shifts. The point at which extra vehicle movements, extra staff or extended hours tip a use over the line is set case by case, which is why intensification produces so many enforcement disputes. Hours and delivery times on their own rarely create a change of use. They are normally controlled by condition on the existing permission instead.

Illustrative example

An illustrative case: a bakery in a parade of shops, Class E(a), selling bread and sandwiches. The owner adds a fryer, a hot counter and a moped bay, and by month six two-thirds of turnover is hot food collected or delivered in the evening. The use class has not changed on paper. In character it has moved from a daytime shop serving a footfall trade to an evening hot food operation with vehicle activity, cooking odour and late servicing. That is the pattern councils treat as a material change, and the honest answer is that the fryer alone would not have done it.

The evidence a council will ask for

Where the position is disputed, the argument is won on documents, not adjectives. The bundle that carries weight looks like this:

• Dated photographs of the frontage, the interior layout and any plant.
• The decision notice and conditions for the last permission on the unit.
• Business rates records showing the description and the period of assessment.
• Leases, licences and tenancy agreements showing occupation and extent.
• Till or accounting records splitting revenue by type of sale, which is what settles a hot food argument.
• Delivery notes, waste transfer notes and staff rotas showing servicing patterns and hours.
• Statutory declarations from people who can speak to the use over time.

A council will weigh this on the balance of probability. Records made at the time beat recollections made afterwards, and a gap in the sequence is usually read against the applicant.

What to do when the position is arguable

Do not gamble on it. A change of use that turns out to be material and unauthorised exposes you to an enforcement notice, and the ten-year immunity period under the Levelling-up and Regeneration Act 2023 changes gives a council a long window in which to act. Check whether that change is in force before you rely on any time limit.

The formal route is a certificate of lawfulness of proposed use or development under section 192 of the 1990 Act. You describe the use precisely, the council decides whether it would be lawful, and a positive certificate is conclusive. It costs less than a planning application, takes less time, and involves no policy judgement.

Where the answer is that permission is needed, the supporting documents follow the concerns the use raises. A hot food or restaurant use points to odour and extraction work, a gym or a bar points to noise, and a use with vehicle activity points to transport and parking evidence. Browsing the full list of report types against your own use is a faster way to scope that than reading a validation list cold. Changes of use can also create a levy liability where new floorspace is created, so check how community infrastructure levy liability arises before you assume a conversion is free of charges.

This is general guidance, not legal advice; check the position with your local planning authority or a qualified professional before relying on it. A certificate of lawfulness is the only formal way to confirm that a use is lawful.

Enter your postcode on PlanScope to see which reports a change of use at your unit is likely to need.

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