Pepper-potting and cluster limits in affordable housing

Pepper potting in affordable housing means scattering the affordable homes singly or in twos across a scheme instead of grouping them in one block or one corner of the site. Local plan policies ask for it so that tenure is not legible from the street. Registered providers resist it because a home they manage in the middle of a market terrace costs more to maintain, repair and let than the same home next to its neighbours. The usual settlement between those two positions is a cluster limit: dispersal, but in small groups rather than one at a time.

Getting that number agreed early changes the layout. Agree it late and you redraw.

What pepper-potting means on a drawing

On a house scheme, pepper-potting shows up as affordable plots distributed through the street pattern with market plots either side, sharing the same frontage treatment, the same boundary detail and the same parking arrangement. On a flatted scheme it means affordable flats on the same cores and the same floors as market flats, using the same entrance, lift and bin store.

The opposite is a single affordable block, often at the back of the site, often with its own access and its own bin store, and usually with a reduced external specification. That arrangement is what the policy exists to prevent.

In between sit the arrangements most consented schemes actually use: affordable homes in groups of two to six, spread across the site, with tenure undetectable from outside. A plan annexed to the section 106 agreement records which plot is which, and the Affordable Housing Statement explains how the distribution meets the policy.

Why authorities ask for dispersal

The planning case rests on the social objective in the National Planning Policy Framework (August 2026 edition), which asks for mixed and balanced communities, and on local plan policies that translate that into a distribution requirement. The arguments run as follows.

Concentration produces identifiable blocks that attract stigma, which affects lettings, resale values on the market units and the reputation of the estate. Dispersal also spreads the tenure across the parts of the site with better aspect, closer play space and more convenient parking, rather than leaving affordable homes with the leftovers. And where an authority has been through an examination on this point, the policy wording tends to be specific about distribution, because inspectors press for clarity on anything that affects deliverability. The record of how that wording was settled sits in the main modifications at a local plan examination.

There is a design argument too, and it is the strongest one. A layout where tenure drives the elevation produces a scheme that reads as two developments stitched together. Authorities see a lot of those.

Why registered providers push back

The objections are operational and they are legitimate.

• Repairs and maintenance are priced by visit. Twelve homes in one terrace is one visit; twelve homes scattered across 40 plots is twelve.
• Grounds maintenance and communal cleaning contracts become unworkable where the provider's responsibility is a series of islands inside a management company's area.
• Service charges on flats are calculated by block or by core. A single affordable flat on a market core means the provider pays a share of charges it cannot control, and shared ownership leaseholders carry that charge personally.
• Lenders and valuers treat single units inside market blocks cautiously on shared ownership, which affects sales rates.
• Housing management, including tenancy enforcement and antisocial behaviour, is harder where the provider has no presence in the immediate group.

None of that is an argument against dispersal in principle. It is an argument against the extreme version, where no two affordable homes adjoin. Providers will usually say so plainly at the heads of terms stage, and if they do not, the applicant finds out at the point the agreement is signed and the provider walks away from the price.

Cluster limits as the workable compromise

A cluster limit sets a maximum number of affordable homes in any contiguous group, and sometimes a minimum too. Policies and agreements express it in a handful of ways.

The number that gets agreed depends on who is taking the homes. A traditional rented provider with local stock may accept groups of two. A provider taking a small allocation from outside the area will want a bigger minimum. Ask the question before the layout is fixed, because moving a plot from affordable to market after submission changes the mix and may need a section 73 application, which is a slower and more exposed route than it sounds. The practical constraints on that are set out in the guide to section 73 variation of planning conditions.

Tenure blind design and the entrance problem

Tenure blind means the external treatment does not reveal tenure. Same brick, same windows, same doors, same rainwater goods, same boundary treatment, same bin and cycle store detail. Where a policy requires it, the authority will compare the plot schedule against the elevations and will notice if the affordable plots have a lower grade window or a different front door.

Flats raise the entrance question. A separate affordable entrance to a shared building attracts criticism, and some policies now forbid it outright. The honest difficulty is that a single entrance means shared communal areas, shared service charges and shared management, which brings back every objection in the previous section. Resolving it usually means a legal structure where the provider pays a fixed or capped contribution to the management company, agreed before the layout is settled rather than after.

Internal specification is treated differently. Most policies accept variation in kitchen and bathroom finishes, floor coverings and white goods, provided the homes meet the same space standard and the same accessibility requirement.

An illustrative distribution across one phase

The following is illustrative only, not a worked case from a real scheme. Take a phase of 48 homes with a policy requirement of 25 per cent affordable, so 12 homes, and a cluster limit of no more than four.

A distribution that satisfies both might place four affordable homes as a short terrace on the main street frontage, three as a group fronting the public open space, three as a pair plus a single adjoining the parking court, and two at the end of a market terrace. That is four locations, the largest group of four, every home on the same frontage specification as its neighbours, and a tenure plan that a provider's development surveyor can price.

The same 12 homes as one block of 12 at the rear would meet the numerical requirement and fail the distribution policy. Twelve single homes with no two adjoining would meet the distribution policy and would probably lose the provider.

Drafting the requirement into the agreement

The section 106 agreement is where the arrangement becomes enforceable, so the words have to be capable of being applied by a monitoring officer three years later.

1. Define the affordable homes by plot number against an annexed plan, and give that plan a drawing number and revision.
2. State the cluster limit in the definition, not in a recital, and say whether corner-to-corner contact counts as contiguous.
3. Include a substitution mechanism allowing plots to be exchanged for equivalent plots with the authority's written approval, so a construction sequencing change does not need a fresh application.
4. Tie the trigger to occupation of market homes, with a stated proportion of affordable homes transferred before a stated proportion of market homes is occupied.
5. Deal with the service charge and management regime in the same schedule, including any cap on the provider's contribution.
6. Say what happens if no registered provider can be found on the stated terms, and what evidence of marketing the authority will accept.

Where the cluster limit is the thing that makes the scheme unviable, that has to be demonstrated through a Viability Assessment prepared on the national guidance, and councils expect a suitably qualified author for that work with professional review strongly advised. Asserting the point in correspondence will not carry it.

This is general guidance, not legal advice; check the position with your local planning authority or a qualified professional before relying on it. If you are assembling the supporting documents for a scheme with an affordable requirement, PlanScope can draft the statement from your scheme data: browse the report types to see what the application needs.

PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.