Change of use is the process of altering how a building or part of a building is used in planning terms, and it often runs alongside commercial design work such as a fit-out or shopfront alteration. Whether you need planning permission depends on the current and proposed "use class" — the category that planning law assigns to a property — and whether the change is permitted automatically. This guide explains how those classes work, when approval is required, and what tends to be involved in small commercial projects.
What counts as a change of use?
A change of use happens when the way a property is used moves from one planning category to another. Turning a shop into a café, an office into a flat, or a warehouse into a gym are all common examples. The physical building may stay the same; it is the activity inside that changes.
Not every change is significant in planning terms. Minor shifts within the same category are usually unaffected, and some changes are allowed without a formal application. The test is whether the new use is "materially different" — a meaningful change in character, intensity or impact on neighbours, traffic, noise or hours.
Where a change is material and not otherwise permitted, planning permission is normally needed before it takes place. Using a building for the wrong purpose without consent is a breach of planning control. A local planning authority can, in some cases, take enforcement action, so it is worth confirming the position early.
Use classes and permitted changes
This guide explains how those classes work, when approval is required, and what tends to be involved in small commercial projects.
England groups property uses into classes under the Use Classes Order. The structure was reformed in 2020, and the broad Class E now covers a wide range of commercial, business and service uses — shops, cafés and restaurants, offices, clinics, gyms and certain light industrial activity. Other classes sit outside this, including pubs and hot-food takeaways, and several uses are "sui generis", meaning they belong to no class at all.
The practical effect is that many switches inside Class E no longer need a planning application. A shop can become an office, or a café can become a clinic, without a change of use being triggered, because both fall within the same class. This gives high-street premises more flexibility than the previous system allowed.
Other changes are handled through "permitted development rights", which grant consent for specified moves subject to conditions. A common route allows certain commercial buildings to become homes, often through a process called prior approval. That is not the same as full permission: the authority checks defined matters — such as flooding, contamination, noise and natural light — rather than the principle of the change itself.
Some points are worth checking before assuming a change is permitted:
- Whether the building lies in a conservation area, where rights are often restricted.
- Whether the property is listed, which adds a separate consent regime.
- Whether an "Article 4 direction" has removed permitted development rights locally.
- Whether size limits, vacancy periods or other qualifying conditions apply.
- Whether the rules in Scotland, Wales or Northern Ireland differ, as the use classes systems are not identical across the UK.
Because the regime is detailed and changes periodically, many people ask the local planning authority for confirmation. A lawful development certificate can establish in writing that a proposed use or change is lawful without permission, which is useful evidence for lenders and future buyers.
Shopfronts, fit-outs and small offices
A change of use rarely happens in isolation. New occupiers usually want the interior reworked and, on the high street, the frontage updated. These design elements carry their own approval requirements that sit alongside the planning position.
Shopfront design is often the most visible part of a project. Replacing or altering a frontage in a conservation area, or on a listed building, normally needs planning permission and may need listed building consent. Signage and illuminated fascias are controlled separately under advertisement regulations, with limits on size, lighting and projection. An architect or designer will typically check whether the proposed frontage respects the proportions and materials of the building and the surrounding street.
Internal fit-outs — the works that adapt a space for its occupier — raise different issues. Building regulations apply to most structural, fire, ventilation and accessibility works, regardless of whether planning permission is required. Fire safety, means of escape and step-free access are frequent considerations in commercial spaces used by the public.
An office fit-out commonly involves new partitions, services and finishes. Even where the use class does not change, the layout must meet fire-separation and escape standards, and provide adequate facilities. Mechanical ventilation, acoustic separation between tenants, and accessible WCs are typical points a designer will address at an early stage.
A mixed-use scheme — combining, for example, a commercial unit at ground level with flats above — adds further complexity. Residential and commercial uses have different requirements for sound insulation, fire compartmentation and private amenity space. Where homes are created, planning permission or prior approval is usually involved, and the residential parts must meet space and daylight standards that do not apply to commercial floors.
Across these projects, several approvals can run in parallel: planning permission or prior approval, building regulations, advertisement consent, and sometimes listed building or conservation area consent. A surveyor or architect will often coordinate these, advising on which apply and in what order. Establishing the use class, the existing lawful use and any local restrictions before design begins helps avoid abortive work later. It is sensible to confirm the planning position in writing before committing to fit-out costs.
Updated: June 2026