How to keep a planning permission alive: why lawful development certificates matter more than many developers realise

One of the most common reasons a planning permission is lost has nothing to do with planning policy, design or local opposition. It is simply that the permission expires before it has been lawfully implemented.

​

For developers and landowners, the consequences can be significant. A permission that has already secured planning approval may need to be submitted again under a different policy context, exposing the scheme to changing planning policies, additional costs and delays, with no guarantee that the same outcome will be achieved.

​

Recent projects at Maddox Planning suggest this is a risk that is often underestimated. Several Certificates of Lawfulness we have prepared over the past year have centred on a common question: was the planning permission lawfully implemented before it expired?

​

Although every case turns on its own facts, they all demonstrate the importance of treating implementation as a planning strategy rather than simply a construction milestone.

​

A common misconception is that substantial building works must have begun before a permission can be preserved. In reality, planning law asks a different question. Has a "material operation", as defined by section 56 of the Town and Country Planning Act 1990, been carried out before the permission expires? That definition extends well beyond the construction of the building itself and can include demolition, excavation for foundations, laying foundations and other specified operations. The issue is therefore not how much of the development has been built, but whether the statutory test for commencement has been met.

​

That principle lay at the heart of recent projects in Richmond, Lambeth and Havering. In each case, relatively early site works formed the basis of a Certificate of Lawfulness application intended to confirm that the permission had been implemented within the required timescale. The individual circumstances differed, but together they illustrate an important point: implementation is rarely judged by appearance alone. It is judged against the approved permission, the conditions attached to it and the evidence demonstrating what happened on site.

​

The conditions attached to a planning permission are often where difficulties arise. Developers sometimes assume that carrying out physical works is enough to keep a permission alive. However, where pre-commencement conditions remain outstanding, works that might otherwise amount to implementation may not lawfully preserve the permission. Understanding the sequencing of condition discharge and commencement is therefore just as important as deciding when contractors arrive on site.

​

Evidence is equally critical. A local planning authority determining a Certificate of Lawfulness is not reconsidering the planning merits of the development. Instead, it is assessing whether the evidence demonstrates, on the balance of probability, that lawful commencement took place before the permission expired.

​

That is why contemporaneous records matter. Dated photographs, contractor statements, invoices, site diaries, correspondence and other project records can all contribute to demonstrating what happened and when. Individually, they may tell only part of the story. Taken together, they can provide a persuasive account of lawful implementation.

​

Leaving implementation until the final days before expiry inevitably increases risk. Even where the necessary works are completed in time, assembling sufficient evidence afterwards can become unnecessarily difficult. Contractors move on, records are misplaced and memories fade. What could have been a straightforward exercise can quickly become a complex evidential one.

​

A Certificate of Lawfulness can remove much of that uncertainty. By formally confirming that a planning permission has been lawfully implemented, it provides clarity not only for the developer but also for purchasers, funders and professional advisers undertaking due diligence in the future. Where development is phased or delayed by market conditions, that certainty can have real commercial value.

 

The wider lesson is that implementation should never be treated as an administrative exercise undertaken shortly before a permission expires. It should form part of the project's planning strategy from the outset. Identifying the material operation that will constitute commencement, understanding which conditions must first be discharged and ensuring appropriate evidence is retained are all relatively straightforward steps if considered early enough.

​

Planning permissions are valuable assets. Protecting that value depends not simply on beginning work before the deadline, but on ensuring that commencement is lawful, properly evidenced and capable of being demonstrated if questioned in the future. For many developments, a small amount of planning ahead before implementation can avoid the far greater cost and uncertainty of having to seek planning permission all over again.