Planning law update 2025

Change of use issues—the planning perspective

Joanna Crow
Joanna Crow
5 min Read

Legal director Joanna Crow explores how material changes of use can become lawful in the absence of planning permission.

If you carry out development (as defined in s.55 Town and Country Planning Act 1990), you will usually need planning permission. Without it, the development may be unlawful and subject to enforcement action. There are two limbs of ‘development’:
  1. operational works (building, engineering works) and 
  2. material change of use
This article looks at the second limb: material changes of use. In particular, it examines some of the common issues that arise when considering whether the use (existing and/or proposed) of a property is lawful, where there is no planning permission for that use, and permitted development rights for proposed material changes of use which can be exercised under the GPDO (The Town and Country Planning (General Permitted Development) (England) Order 2015 – GDPO).

Long use immunity

In the absence of planning permission authorising the current use of a property, its use can become lawful by long use. Long use immunity from enforcement occurs under s.171B of the Town and Country Planning Act 1990, after which ‘no enforcement action may be taken’. In practice, this means that once the immunity is achieved, the use which has continued throughout this time is now lawful use. The time limit for long use immunity is 10 years from the date of the use (unless the use began before 25 April 2024 for use as a dwelling house in which case it will be four years.)

Use must be continuous and uninterrupted, but note that there is complex case law on determining continuity: for example, holiday chalets do not require year-round use for continuity to be established. Once the new lawful use has crystallised, continuity need not be maintained for the same use to remain lawful at a later date, provided that the use is not subsequently abandoned or subject to a further material change of use.

In terms of evidencing that a material change of use has accrued over 10 years, the following may be helpful: occupation agreements (e.g. leases) – permitted user clauses; agents’ brochures (historic and current); schedules of dilapidations (can contain details of uses and floorplans); licences to alter (can contain details of works carried out to facilitate a use); business rates records (can have breakdown of uses of floorspaces); and sales/distribution contracts. These can all be useful evidence to determine lawful use.

Where there is 10 years of continuous lawful use, it can sometimes be helpful to make a certificate of lawful existing use or development (CLEUD), whereby, if granted, the local planning authority (LPA) confirms the use as lawful. This can be an appropriate strategy if future planning applications need to be made and it is therefore important to establish what the baseline lawful use comprises and/or to assure future buyers. An alternative is to obtain indemnity insurance against the risk of enforcement action, premiums for the same usually being low if there is robust, clear evidence of 10 years’ use.

Where applicants apply for a CLEUD, the evidence should be precise and unambiguous, and the determination is made on the balance of probability, meaning that the LPA should usually grant these if they do not have any evidence to contravene an application. Russell-Cooke's planning team regularly acts on such CLEUD applications.

Permitted development rights for changes of use: prior approvals

Changes of use pursuant to the GPDO are increasingly common. If this route is being considered, careful consideration should be undertaken as to the relevant permitted development rights. In particular, check the planning history to ascertain:
  • any relevant planning permission which has authorised the current building that could have removed these rights (precise wording of any such condition is important)
  • whether the current use is lawful (if not lawful, then the relevant permitted development right to change from the same may not be available)

For conversion schemes that fall within the Environmental Impact Assessment Regulations (generally more than 150 residential units), an EIA screening process must also be undertaken ahead of reliance on any permitted development right or prior approval.

For some permitted development rights in the GPDO, a prior approval application to the LPA is required before reliance can be made on the relevant permitted development right. In common with CLEUD applications, prior approval applications are not determined by reference to policies in the development plan; only the criteria set out in the GPDO are considered, albeit some of those criteria allow reference to specific development plan policies.

One of the most common permitted development rights for property developers which requires a prior approval application is Class MA of the GPDO – commercial, business and service uses to dwellinghouses. These applications have recently hit a record high due to relaxation of restrictions and availability of office space following increasing remote working.

Class MA can be an effective and efficient way of repurposing disused office space, providing residential accommodation without the emissions or costs involved in new-build development. However, there are things to consider for developers, and not all office blocks will lend themselves to the amenities required for residential accommodation. LPAs will need to consider the impact from remaining commercial premises when deciding applications in areas important for certain commercial uses, availability of natural light, and minimum space standards.

A particular requirement of Class MA (and several other permitted development rights) is the need to complete the development within three years. Depending on the quantum of conversion works, this can be challenging. If the conversion works are not completed within that time frame, there is a risk of enforcement action; this can impact future sales or occupation of those residential units. While section 73 applications can be made to extend the time for completion of the development, there need to be strong reasons for the delay which lie outside the control of the developer.

Conversions for high-rise buildings via the prior approval route can be challenging, as the same require building control approval from the Building Safety Regulator before construction can commence, and delays here can significantly eat into the programme for conversion works. It is also important to note that planning permission can be separately required for facilitating operational works depending on the particular permitted development right. This should be obtained before any works commence.

Developers will need to consider section 106/CIL obligations which can arise to mitigate the impacts of the development. CIL obligations are a particular area of concern where office buildings have fallen out of use over time, as the ability to offset in-use floorspace from the CIL charges attaching to an office-to-residential conversion will be unavailable if the offices have not been in lawful use for a continuous period of at least six months within the last three years.

Joanna Crow is a legal director in the real estate, planning and construction team, advising on the full spectrum of development work involving residential, commercial and mixed-use schemes as well as advising on consortium and strategic land.

Get in touch

If you would like to speak with a member of the team you can contact our real estate planning and construction solicitors; Holborn office (Email Holborn)  +44 (0)20 3826 7523; Kingston office (Email Kingston) +44 (0)20 3826 7518; Putney office (Email Putney) +44 (0)20 3826 7518 or complete our form.

Briefings Real Estate, planning and construction change of use changes of use planning permission operational works material change of use The Town and Country Planning (General Permitted Development) (England) Order 2015 (GPDO) GDPO GDPO 2015 long use immunity CLEUD CLEUD application Joanna Crow