Can you combine a planning permission with your permitted development rights?
This is a surprisingly common issue.
Many clients come to us having carried out an extension partly under a planning permission and partly under permitted development rights. On the face of it, this seems perfectly sensible. If you have planning permission for one element of a scheme, and permitted development rights for another, why not implement both?
The difficulty is that, in most cases, you cannot.
The basic rule
It is not generally possible to build part of an extension under planning permission and part under permitted development rights where the two come into physical contact.
Once they do, the development needs to be assessed as a whole under a single planning permission.
This often comes as a surprise. Clients will have obtained a lawful development certificate for a roof extension, planning permission for a rear extension, and assume that both can be built together. In practice, once those elements form a single combined structure, permitted development rights can no longer be relied upon in that way.
Why this happens so often
Planning is complicated and building work is rarely straightforward.
Most people do not set out to breach planning control. They obtain the necessary approvals, instruct a builder and proceed in good faith. Changes are then made on site, or different elements of a scheme are implemented together, without realising that this creates a problem.
It is also a common misunderstanding. The planning system does not make this point particularly clearly, and many people assume that if each element is lawful on its own, the combined result must also be lawful.
When does it become a problem?
People do this all the time without any difficulty.
The issue only arises if the council becomes aware of it, usually following a complaint from a neighbour. At that point, the enforcement team will look at the development as a whole and assess whether it has planning permission.
If it does not, you may be asked to submit a retrospective planning application, or in some cases face formal enforcement action. You can read more about planning enforcement here.
Real examples
We recently dealt with a case of this kind in Lambeth, where a client had built a rear extension under planning permission and a roof extension under permitted development, with the two forming a single combined structure.
The council warned that enforcement action would be taken. We prepared ‘as built’ drawings and submitted a retrospective planning application, supported by a detailed planning statement. Planning permission was ultimately granted, avoiding the need for alterations or demolition.
In a similar case in Barnet, our client had built extensions that were shown on various permissions but where there was no single concept for the whole project. The council invited a retrospective planning appeal, but then refused it. We were delighted to win the subsequent appeal.
What can be done?
That will depend on the circumstances.
In many cases, the appropriate approach is to submit a retrospective planning application for the development as built. This allows the council to assess the scheme as a whole, rather than as separate elements.
If permission is refused, there may be a right of appeal. In other cases, it may be possible to amend the development or to pursue a different strategy. If you are already facing enforcement action, you can read more about your options here.
A practical point
If you are planning an extension that combines different elements, it is worth thinking about this issue at the outset.
If the scheme is likely to form a single combined structure, it is usually better to secure planning permission for the whole development rather than relying on a mixture of permissions and permitted development rights.
Getting advice
This is a technical area, but it arises surprisingly often.
If you have already carried out works in this way, or are being contacted by the council about it, it is usually worth taking advice before the situation escalates.
