The planning unit - Know your limits

When determining whether a material change of use of land or buildings has taken place, what is the most appropriate physical area against which to assess the materiality of the change or, in short, what is the

On the face of it, this is quite a simple question and the Court will generally look at it as 'a matter of common sense' using the unit of occupation itself as a starting point. However, the answer is often far from black and white and necessitates specific consideration on a case by case basis as a material change of use of a planning unit will often require express planning permission from the local planning authority.

The three tests

While the Court never intended them to become exhaustive tests to cover every situation, three tests for determining the planning unit were laid out by Bridge J in Burdle v. Secretary of State for the Environment, as follows:

  1. First, whenever it is possible to recognise a single main purpose of the occupier's use of his land to which secondary activities are incidental or ancillary, the whole unit of occupation should be considered.
  2. Secondly, it may equally be apt to consider the entire unit of occupation even though the occupier carries on a variety of activities and it is not possible to say that one is incidental or ancillary to another. This is well settled in the case of a composite use where the component activities fluctuate in their intensity from time to time but the different activities are not confined within separate and physically distinct areas of land.
  3. Thirdly, however, it may frequently occur that within a single unit of occupation two or more physically separate and distinct areas are occupied for substantially different and unrelated purposes. In such a case each area used for a different main purpose (together with its incidental and ancillary activities) ought to be considered as a separate planning unit.

The first test - Ancillary use

The first test is intended to cover ancillary uses of land. Take, for example, a large retail store with a small area of office space used to facilitate the processing of the retail store's paperwork, with both areas (i.e. the store and the office space) being within the same occupation. Under this first test, the whole of the retail store, including the office space, will be considered the planning unit.

There are, however, exceptions to this principle. In 2002, for instance, on an appeal from the Secretary of State, the Court ruled against Harrods' application for a lawful development certificate for the proposed use of the existing roof of the company's store in Knightsbridge for a helicopter landing.

The helicopter landing was to be used solely by the owner of the store in connection with his role as chairman and his work in directing the day-to-day operations of the store. In making his decision, the Secretary of State regarded "ordinary and reasonable practice" or what was "normally done" at inner city department stores and decided that the use of the roof as a helicopter landing was not incidental or ancillary to the use of the department store. The Court refused to overturn the Secretary of State's decision and considered that he was entitled to come to that conclusion meaning that the store and the roof were separate planning units.

The second test - Composite use

The second test is intended to cover 'composite' uses of land. Take, for example, use of land as a vehicle dealership including elements of retail use, storage, offices and staff facilities, all within the same occupation. Under the second test, the entire vehicle dealership will be considered the planning unit.

However, that is not to say that you can intensify, cease or add a use so that there is a material difference in the overall mix of uses operating within a composite use planning unit without planning permission. Taking the above example, the addition of a substantial car repair service at the vehicle dealership may constitute a material change of use of the planning unit necessitating planning permission.

The third test - Separate planning units

Finally, the third test is intended to cover separate planning units within the same building. Take for example individual flats within a residential block, under the third test each flat will be considered a separate planning unit. This approach was confirmed by the Court in a case concerning the Metro Centre in Gateshead where each individual shop was considered to be its own planning unit.

Physically separate and distinct areas, however, will not always be considered separate planning units, provided that they are used for similar and related purposes. For example, in 1997, the Court held that an Inspector was entitled to conclude that the co-ordinated pattern of the use of five parcels of land for markets overrode their physical separation and disunity of ownership such that they were in fact one planning unit. The parcels of land in question were owned by three separate parties and were, in places, split by a main road and a small slither of other land.

The examples given above can be difficult to reconcile. Accordingly, the answer to the question of what is the planning unit, as noted by Bridge J in Burdle, 'must be a question of fact and degree' to which the decision taker applies his or her mind on a case by case basis.


This information is for general information purposes only and does not constitute legal advice. It is recommended that specific professional advice is sought before acting on any of the information given. Please contact us for specific advice on your circumstances. © Shoosmiths LLP 2024.



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