Reports needed for an out of centre retail unit

An out of centre retail unit needs two documents that no other development type requires: a sequential test and, above the relevant floorspace threshold, a retail impact assessment. Everything else in the pack follows from the site rather than the use. Get those two wrong and the rest of the evidence base does not matter, because national policy directs main town centre uses to centres first and requires a proposal that fails the sequential test to be refused.

The national default threshold for an impact assessment is 2,500 square metres of gross floorspace for retail and leisure development outside a centre, unless the local plan sets a different figure. Many plans set a much lower one, sometimes a few hundred square metres in areas with fragile centres, so the local plan is the first document to read.

The national floorspace threshold and local variations

Start by establishing three things from the adopted plan: whether the site is in a defined centre, whether the plan sets a local impact threshold, and whether the site is allocated for the proposed use.

If the site is in a centre and the use is appropriate to it, neither test applies. If the plan allocates the site for retail and the allocation is up to date, the sequential test generally does not apply either, because the plan has already done the exercise.

Everything else is out of centre or edge of centre development, assessed on the sequential approach and, above the threshold, on impact. Edge of centre is a defined term, usually taken as within 300 metres of a primary shopping area for retail, and being edge of centre helps with the sequential test rather than removing it.

The sequential test and the sites that must be considered

The test asks whether the proposed development could be accommodated on a sequentially preferable site, in order: in centre, then edge of centre, then out of centre in a location that is accessible and well connected to a centre.

The search area has to be defined and justified, usually by reference to the catchment the proposal serves. Then every site within it that could physically accommodate the development is assessed for availability, suitability and viability, with the evidence set out site by site rather than as a conclusion.

Two points decide most sequential tests. The first is flexibility: an applicant is expected to demonstrate flexibility on format and scale, so a proposal that can only work as a single 3,000 square metre box on one floor with 150 parking spaces will struggle unless the operational reasons are explained in detail. The second is timing, since a site that is available within a reasonable period counts even if it is not available today.

Present the Sequential Test (Retail) as a schedule with a plan showing the search area, every site considered, and a short assessment of each against the three criteria. A narrative that names three sites and dismisses them in a paragraph is the version that gets challenged.

Impact on planned investment and vitality

Where the threshold is crossed, the impact assessment has two limbs, and both have to be addressed separately.

The first is the impact on existing, committed and planned public and private investment in a centre or centres in the catchment. That means identifying schemes with permission, sites allocated in the plan, and investment the council has publicly committed to, then assessing whether the proposal would undermine them.

The second is the impact on town centre vitality and viability, including local consumer choice and trade in the town centre and the wider retail catchment. National policy sets the assessment period at five years from the time the application is made, extended to ten years for larger phased schemes.

Neither limb is a pass or fail calculation. The policy test is whether the impact would be adverse to a degree that outweighs the benefits, and a Retail Impact Assessment that reports a trade diversion percentage without relating it to the health of the affected centre has done half the job.

Catchment, turnover and trade draw evidence

The quantitative work rests on four inputs, and the assessment should state each one with its source:

• the catchment definition, usually drawn from drive time isochrones or an existing household survey
• population and expenditure per head, taken from published projections rather than assumed
• the turnover of the proposal, derived from company average sales densities for the operator type or from published benchmarks
• the trade draw, that is where the turnover is drawn from, expressed as a diversion from named centres and stores

A household survey commissioned for the application gives the strongest evidence and costs the most. Where an existing survey for the local plan is recent enough, using it is normally accepted, and it has the advantage that the council's own evidence base produced it.

Then set the diversion figures against a health check of the affected centres: vacancy rates, the mix of uses, footfall where data exists, and any recent closures or investment. A 6 per cent diversion from a healthy market town is a different matter from the same figure applied to a centre with high vacancy, and the assessment has to say which situation it is describing.

Transport, parking and linked trips

A retail unit generates trips at the worst times for the network: Saturday afternoons and weekday evening peaks. Expect the highway authority to ask for a Transport Assessment with a Saturday peak analysis as well as the standard weekday model.

Parking provision cuts both ways. Too little and the highway authority objects. Too much and the council argues the scheme is designed to draw trade from a centre where parking is charged, which feeds directly into the impact case.

Linked trips are the argument that most often rescues an out of centre proposal, and they need evidence rather than assertion. Where the unit sits next to existing retail, a survey showing how many customers visit more than one destination is worth having, and where it is isolated the honest position is that linked trips will be limited.

Design, servicing and frontage

Out of centre retail is usually refused on planning policy rather than on design, but the design evidence still has to work.

Show the service yard with swept paths for the largest delivery vehicle, the refuse and recycling arrangements, the customer entrance in relation to the pedestrian approach from the nearest bus stop, and cycle parking at the door rather than at the edge of the car park. Where the unit fronts a road, an active frontage and a genuine pedestrian route from the footway matter more than the elevation treatment.

Servicing hours will be conditioned wherever there are residential neighbours, and an early acoustic view on early morning deliveries saves an argument later.

The document bundle to submit

For a typical out of centre unit above the impact threshold, the pack runs to a planning statement, the sequential test, the retail impact assessment, a transport assessment and travel plan, a design and access statement, a drainage strategy, a noise assessment, an air quality assessment, a lighting assessment, a preliminary ecological appraisal with the statutory biodiversity metric, a construction management plan and a waste management strategy. Add a flood risk assessment where the site is one hectare or more or in flood zone 2 or 3.

Where the proposal includes other Class E uses alongside the shop, the mix affects both the sequential test and the impact case, and the considerations that apply to a medical or professional use in a shop unit apply alongside the retail tests. The report index lists the rest.

Conditions on goods sold and subdivision

Assume the permission will be conditioned, and negotiate the wording rather than inheriting it.

The common conditions restrict the range of goods sold, often by reference to a convenience and comparison split with a maximum net sales area for each, prevent subdivision into smaller units without further permission, prevent the installation of a mezzanine, and fix the maximum net sales area overall.

Those conditions exist because the impact case was built on a particular type and scale of trading, and a council that grants an unrestricted permission cannot control what the unit becomes. A condition restricting the use is still enforceable even though Class E allows movement between uses, which is the point operators most often misunderstand.

Ask for the restriction to be drawn around the operational need rather than the operator's name. Conditions tied to a named retailer cause problems at the first change of tenant, and they are not the way the policy test was framed.

And where the scheme is close to the threshold, consider whether reducing the floorspace below the local figure is worth more than the space it costs.

PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval. This is general guidance, not legal advice; check the position with your local planning authority or a qualified professional before relying on it.