Phasing a scheme to stay below a threshold

Phasing a scheme is ordinary development practice. Phasing it to sit below a threshold is a different exercise, and the question is whether the threshold is assessed on the application in front of the authority or on the project as a whole. For environmental impact assessment the answer is the project, which is why phasing to avoid a planning threshold fails there more often than anywhere else. For the major development definition, the fee bands and the biodiversity small sites route, the answer is closer to the application, and local plan policies increasingly close that gap with aggregation wording.

Legitimate phasing against threshold avoidance

Phasing exists for good reasons. Cash flow, infrastructure sequencing, sales rates, the time it takes to secure a highway agreement, and the practical impossibility of building 200 houses at once.

The distinction a decision maker draws is about the project rather than about your motives. If the land, the access, the drainage and the market are one scheme, it is one project, and applying for half of it does not make it two. If phase two depends on land you do not control, on a different access and on a separate planning case, that is a separate project in substance.

Three tests tend to decide it in practice. Functional interdependence: can phase one operate without phase two? Physical connection: shared access, shared drainage, shared open space. And intention at the time: a masterplan, a promotion agreement or a board paper describing the whole site.

The risk of getting it wrong is not a refusal. It is a permission that a third party can challenge, and a challenge on project splitting goes to the lawfulness of the decision rather than to its merits.

How a phased outline permission handles thresholds

An outline application for the whole site with a phasing plan is the cleanest route, and it is usually the cheaper one too.

Thresholds are then assessed on the whole scheme at outline stage. The application is major development, the full evidence base is required once, and the reserved matters applications that follow deal with detail rather than principle. A phasing condition fixes the sequence, and the infrastructure triggers sit in the obligation.

What this route costs you is the evidence base up front. A transport assessment for 180 units, a full ecology package and a drainage strategy for the whole site are required before the first house is sold. What it buys you is certainty, and a defensible position if anyone asks whether the project was split.

Where the whole scheme is assessed regardless

Several thresholds look at the project rather than the application, and it is worth knowing which.

Environmental impact assessment is the clearest. The regulations require the development to be considered as a whole, and the selection criteria expressly include cumulation with other existing and approved development. An application for part of a larger project is screened against the project.

Habitats regulations assessment works the same way, because the test is the effect of the plan or project alone and in combination.

Affordable housing thresholds are increasingly protected by policy wording. Many local plans aggregate contiguous sites in the same ownership, or sites that form part of a larger developable area, or applications submitted within a defined period. Read the adopted policy before assuming a nine unit application escapes the requirement, and read it alongside the practical points in affordable housing tenure split on major sites.

Referral thresholds have their own rules. In London the Mayor's referable categories are set by regulation and apply to the application as submitted, which is explained in Greater London Authority referable thresholds.

Environmental assessment and project splitting

This is the part where good faith is not a defence.

Screening under the Environmental Impact Assessment Regulations 2017 applies to development of a description in Schedule 1 or Schedule 2, with Schedule 2 thresholds expressed in units, floorspace or site area. An authority screening an application for part of a larger project should screen the project, and if it does not, the permission is vulnerable.

Practically, that means two things for a developer. First, if the whole project would be Schedule 2 development, request a screening opinion for the whole project and get the authority's view on the record. A negative screening opinion for the project is worth far more than silence about a phase.

Second, be straightforward in the application. Describe the wider project, explain the phasing, and let the authority screen what is actually proposed. An Environmental Impact Assessment screening opinion obtained on a full description is a shield. One obtained on a partial description is a liability.

Infrastructure triggers written into conditions

Phasing shifts the question from whether infrastructure is provided to when, and that is a conditions and obligations exercise rather than a threshold one.

Workable triggers are measurable and tied to events the authority can observe: before occupation of the fiftieth dwelling, before first use of the access, on implementation of the phase shown on the approved phasing plan. Triggers tied to unobservable events, such as the start of construction of a particular building, create enforcement problems.

Watch the sequencing traps. An obligation requiring a school contribution on the hundredth occupation, in a scheme where phase two may never be built, leaves the authority short. Expect them to want the contribution earlier, and expect to negotiate about it.

And settle the position on what happens if a later phase does not proceed. A phasing plan that assumes completion, with no fallback for the infrastructure, is the obligation most likely to be renegotiated under section 106A later.

Levy and obligation consequences of phasing

Phasing has a genuine and lawful effect on the Community Infrastructure Levy, and it is the one place where structuring the permission properly pays off.

Where a planning permission is a phased permission, each phase is treated as a separate chargeable development under the levy regulations. That means liability arises phase by phase, payment follows the start of each phase, and the relevant charging schedule and indexation are applied at that point. On a long-running scheme that is a cash flow benefit and an indexation risk at the same time.

It also means the phasing has to be defined in the permission itself. A phasing plan approved later by condition may not achieve the same effect, so take advice on the drafting before the decision notice issues rather than afterwards.

Obligations should follow the same logic: contributions expressed per phase, indexed from a stated date, with triggers tied to the approved phasing plan. An Affordable Housing Statement on a phased scheme needs to show the tenure and the delivery sequence phase by phase rather than as a single total.

Setting out the phasing honestly at the start

The approach that works is also the simplest. Describe the whole project in the application, submit a phasing plan, explain the reasons for the sequence, and ask for a screening opinion on the project rather than the phase.

That produces a decision the authority can defend and you can rely on. It also removes the argument that the phasing was designed to avoid something, because you put the whole thing in front of them.

Where a scheme sits just below a threshold for sound reasons, say that too. There is nothing improper about a nine unit scheme on a site that only supports nine units, and the way to demonstrate it is a layout and a capacity argument rather than silence.

Enter your postcode on PlanScope to see which reports a phased scheme is likely to need at each stage.

This is general guidance, not legal advice; check the position with your local planning authority or a qualified professional before relying on it.

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