What is the 4 Year Rule in Planning Enforcement?


What is the 4 Year Rule in Planning Enforcement?

The ‘4 year rule’ is a term used within town planning, particularly within the planning enforcement specialism, regarding whether enforcement action can be taken against certain types of development (that require planning permission) carried out in breach of planning control. As the name of the rule implies, enforcement action cannot* be taken once 4 years has passed following substantial completion of these certain types of development. 

ET Planning Explain the 4 year rule
The 4 Year Rule

The ‘4 Year rule’, is actually two rules:

  • the first, applies to the carrying out of operational development (or building works); and,
  • the second, applies to the change of use of a building to be used as a dwelling house.

A third rule also exists, the ’10 year rule’, and you can read more about that in a future article, and relates the change in use of land, and non-compliance with planning conditions.

These ‘rules’ are set out in law in the Town and Country Planning Act 1990 (as amended), and the ‘4 year rules’ are set out at Section 171B (1) and (2) respectively, with a couple of exceptions to their application, which you can read more about in a future article. * SPOILER * – you can’t deliberately hide a development for 4 years and then try and claim lawfulness!

Why does the 4 year rule matter?

The 4 year rule matters, because once the rule applies to development carried out in breach of planning control, that development becomes immune from enforcement action and is therefore considered to be ‘lawful’. Once a development becomes lawful, by virtue of the ‘4 year rule’ it is possible to apply for a Certificate of Lawful Existing Use or Development under Section 191 of the Town and Country Planning Act 1990 (as amended). This is particularly important if you’re trying to sell a property, or use a property as collateral for a loan or mortgage – as the value of the property is normally tied to the ‘lawful’ land use, and the only way to ‘prove’ the lawfulness is to seek a Certificate of Lawfulness.

If you happen to live in a dwelling, or you rely on development works that were built or constructed without the proper consents (which could happen for a number of legitimate or innocent reasons), it is very comforting to know that your home or your buildings are not at risk of formal enforcement actions, that could require them to be demolished.

The 4 year rule, and the ability to apply for a certificate of lawfulness to confirm that the 4 year rule has been triggered, is therefore an important part of the planning system to provide assurance to property owners and businesses.

When does the 4 year rule start?

This ultimately depends on the type of development the 4 year rule is being applied, but for operational works the 4 year clock starts to count, when works are ‘substantially’ completed. Whether a building is ‘substantially complete’, is a subjective decision taken by the relevant planning authority, and each case will be slightly different. A decision on each case will need to be considered as a matter of fact and degree, on the unique merits of each circumstance. Normally, as an indicative guide, a new building would normally be considered to be substantially complete when it is made water tight and is capable of its intended end use.

The use of a permanent building as a dwelling house could be considered to start the 4 year clock, when a person (or a family) actively occupy a building as a residence, and have all the facilities you would normally expect in a dwelling. Typically, a dwelling would have some living space (somewhere to live and sleep), an independent access (like a front door), some facility to prepare food (can in some cases be as simple as a fridge and a microwave), and finally some form of washroom and toilet facility. The circumstances around how these different facilities are provided can be very different, and again, each situation is considered on its own merits as part of a subjective judgement by the relevant planning authority.

In the video below, Ben Temple from the ET Planning team provide a simple explanation of the 4 year rule.

The 4 Year Rule | ET Planning Video


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