Lawful commencement: what counts as a material start

A material start on site planning permission is the difference between a live consent and a worthless one. Section 91 of the Town and Country Planning Act 1990 imposes a time limit, normally three years, within which development must be begun, and section 56 says development is begun on the earliest date on which any material operation is carried out. The list of material operations is short, statutory and generous. The trap is not the list. It is the pre-commencement conditions that have to be satisfied before any of those operations can count.

Why a start matters before the permission expires

Once the time limit passes, the permission is gone and cannot be revived. A fresh application is then needed, decided against the policy in force at that later date, which on a site where the development plan has moved on can mean a different answer altogether.

Three other consequences follow from the date of the start.

Community Infrastructure Levy liability crystallises on commencement of the chargeable development, and the Community Infrastructure Levy Regulations 2010 require a commencement notice before work begins. Start without it and the authority can impose a surcharge, withdraw an instalment arrangement and, worse, disapply a self-build or residential extension exemption that had already been granted.

Biodiversity net gain obligations bite at the same point, because the biodiversity gain condition requires the gain plan to be approved before development may begin.

And the clock on any pre-occupation or phasing conditions starts to run, which matters for schemes being built in stages.

The specified operations in section 56

Section 56(4) lists the operations that count as material:

• Any work of construction in the course of the erection of a building.
• Any work of demolition of a building.
• The digging of a trench which is to contain the foundations, or part of the foundations, of a building.
• The laying of any underground main or pipe to the foundations, or part of the foundations of a building, or to any such trench.
• Any operation in the course of laying out or constructing a road or part of a road.
• Any change in the use of any land which constitutes material development.

The last of those is the one people forget. Where a permission authorises a change of use as well as building work, implementing the use can begin the development, and the question of when activity on land crosses into a material change of use becomes the question of whether the permission has been implemented.

Two qualifications apply throughout. The operation must relate to the permission being implemented, so trenches dug for something else do not count. And the courts have accepted that the operation need not be substantial, which is why so much of this turns on evidence rather than scale.

What has been accepted as a material start

The threshold is low. Lower than most clients expect. Digging a short length of foundation trench in the right position, carrying out an initial length of estate road, demolishing a building the permission authorises the demolition of, or laying a service duct to a foundation trench have all been treated as sufficient in practice.

What is consistently not enough: site clearance, removing vegetation, erecting hoardings, installing a site cabin, taking trial pits for ground investigation, pegging out without excavation, and bringing materials to site. None of those appears in section 56(4).

The honest position is that the law rewards a token start, and planning authorities know it. A trench dug on the last afternoon of the three-year period, photographed and witnessed, will usually keep a permission alive. Whether that is a sensible use of a consent is a different question, because a permission kept alive by a trench still has to be built out, and conditions requiring details before particular stages will still be unsatisfied.

Conditions that have to be discharged first

A pre-commencement condition, sometimes called a condition precedent, requires something to be approved or carried out before any development begins. Typical examples are the approval of materials, a construction management plan, a drainage scheme, an archaeological written scheme of investigation, a contaminated land remediation strategy and a tree protection plan.

Since the Neighbourhood Planning Act 2017 inserted section 100ZA into the 1990 Act, a local planning authority cannot impose a pre-commencement condition without the applicant's written agreement, subject to the prescribed procedure. That has reduced their number on new permissions, but older consents are full of them, and the wording matters more than the label. A condition saying "no development shall take place until" is a condition precedent. One saying "prior to the commencement of above ground works" is not, and allows groundworks to begin.

Read every condition before planning a start, and build a schedule listing which are precedent, which are pre-occupation and which are compliance conditions running for the life of the development. On a larger site a Construction Management Plan is often the first thing to submit, because it is both a condition in its own right and the document the authority will want before any other approval.

Starting in breach of a pre-start condition

This is where permissions are lost. Where works are carried out while a condition precedent remains unsatisfied, the long-standing principle is that those works are not a lawful implementation of the permission. They are unauthorised development, and they do not stop the clock.

The courts have recognised limited situations where a breach does not have that effect, including where the condition was discharged, albeit late, within the time limit. The case law is technical and fact-sensitive, so the practical advice is simple: do not rely on an exception. Get the condition discharged first.

Two risk management points.

Submit discharge applications early, with a realistic view of the authority's determination period, and chase them. An eight-week discharge application submitted ten weeks before expiry is a programme risk, not a plan.

Where a discharge application is outstanding and expiry is close, take advice before any work starts. A start in breach can leave a developer with unauthorised works, an expired permission and no route back.

Evidence of the start

Keep contemporaneous proof. If the question is ever litigated, or arises on a sale five years later, the file is the case.

• Dated and geotagged photographs of the operation, showing enough context to locate it against the approved plans.
• A marked-up approved layout showing where the operation took place.
• The contractor's day sheets, plant hire invoices and delivery tickets for that date.
• A short witness statement from the person who carried out the work.
• The commencement notice submitted for levy purposes, with the authority's acknowledgement.
• Copies of the decision notices discharging every condition precedent, dated before the operation.

Local planning authorities now also operate notification duties around the start and completion of development, introduced through the Levelling-up and Regeneration Act 2023 framework and brought in by regulations. Check the current requirements for your authority, because a missed notice is an avoidable breach.

Why section 73 cannot extend a time limit

A common misconception is that section 73 of the 1990 Act can be used to push a time limit back. It cannot. Section 73 expressly excludes varying a condition so as to extend the time within which development must be started, or within which an application for approval of reserved matters must be made.

So the options where a permission is about to expire are narrower than people assume.

1. Make a material start, properly, having discharged the conditions precedent.
2. Submit a fresh application for the same development, accepting that it will be judged against current policy and current levy rates.
3. Where only a minor change is needed, consider the variation routes available, including section 96A for non-material amendments and the newer minor variation provisions introduced by the 2023 Act, whose scope and availability should be checked against the current regulations.

None of those is a substitute for the first. Treat the expiry date as a hard deadline on the programme, work backwards from it through the discharge applications, and add a margin, because discharge applications overrun.

Illustrative example: a permission for nine dwellings expires on 14 March. Conditions 3, 5 and 7 are precedent, covering materials, drainage and tree protection. Discharge applications go in on 2 December, decisions arrive on 28 January and 11 February, and a 6 m length of foundation trench for plot 1 is excavated on 24 February, photographed, and recorded on the groundworker's day sheet. The commencement notice is served the week before. The permission is implemented with eighteen days to spare.

This is general guidance, not legal advice. Check the position with your local planning authority or a qualified professional before relying on it. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval. To see which documents a condition discharge or a fresh application is likely to need, enter the site postcode on PlanScope.