What changes at five dwellings on a single site

Five dwelling scheme requirements land in an awkward gap. The application is still minor development, decided in eight weeks, with no statutory lead local flood authority consultation and no affordable housing contribution in most areas. And yet the council will ask for an evidence base that looks much closer to a major application than to a single house.

The reason is physical rather than procedural. Five dwellings need a shared access, a shared drainage solution, refuse collection that works, and a street frontage that reads as a group. Each of those brings a document with it.

Why five is a practical turning point

Major development starts at ten dwellings, or on a site of half a hectare or more where the number is not known. At five you are comfortably below that, so the 13 week period, the newspaper advertisement and the statutory flood authority consultation do not apply.

Three things change anyway.

The first is shared infrastructure. One house connects to a sewer and a road. Five houses need a drainage system with a defined outfall, an internal road or drive, and a maintenance arrangement that survives the developer's departure.

The second is designated rural areas. National policy sets the affordable housing threshold at ten units, but authorities may apply a lower threshold in designated rural areas, and five dwellings is a common figure. Check the adopted local plan for the policy and the designation before you settle on the number of plots.

The third is scrutiny. A group of five is judged as a piece of townscape, so the council assesses the relationship between the units, the spaces between them and the boundary treatments, rather than each house on its own merits.

Drainage expectations at this scale

The lead local flood authority is a statutory consultee on major development, so at five dwellings its comments are discretionary. Many councils consult anyway, and most ask for a drainage approach with the application.

Work through the surface water hierarchy and show your working. Infiltration first, tested by percolation in accordance with the recognised method and at the right depth, then a watercourse with the riparian owner's or the authority's agreement, then a sewer connection with the undertaker's consent.

A Drainage Strategy at this scale does not need to be elaborate. It needs a plan showing the network and the discharge point, the calculations for storage, the maintenance responsibility, and an exceedance route for when the design event is exceeded.

Maintenance is the question councils ask that applicants answer worst. Name who maintains the attenuation feature and how it is funded: a management company with a deed, an adopting authority, or the individual owners with an obligation in their transfers. An answer left to condition stage tends to produce the weakest of the three.

Foul drainage needs equal attention. The right to connect to a public sewer comes with process, and a build-over agreement is required where the layout crosses an existing sewer. Find the sewer records before drawing the plots, not after.

Ecology and the biodiversity gain plan

Mandatory biodiversity net gain applies to small sites, so a five unit scheme normally carries the gain condition and must deliver a 10 per cent uplift with a 30 year commitment.

The small sites metric can be used where the scheme meets the qualifying conditions, including nine dwellings or fewer on a site under one hectare with no priority habitat present. That simplifies the calculation without removing the need for competent input, because the Biodiversity Net Gain Assessment has to be completed by a competent person and the biodiversity gain plan approved by the authority before development begins.

Self-build and custom build development of nine dwellings or fewer on a site of 0.5 hectares or less is exempt from the gain condition. Five serviced self-build plots can therefore be exempt where five speculative plots on the same land are not, which is worth establishing at the outset because it changes both the budget and the programme.

Survey seasons still bind. Where the site has hedgerows, mature trees, a pond within 500 metres or buildings being demolished, the ecological work may have to wait for a window between spring and late summer, and that delay sits on the critical path rather than beside it.

Highways, access and refuse tracking

A shared access for five dwellings is assessed on visibility splays at the junction, the width and geometry of the drive, turning provision, and whether a refuse vehicle can serve the properties or whether residents must drag bins to a collection point.

Ask the waste service for its requirements before the layout is fixed. The maximum carry distance for bins, the turning circle for the authority's vehicle and the requirement for a reversing manoeuvre or a turning head are all published or available on request, and a layout that ignores them will be redrawn.

Then decide the road's future. A private drive with a maintenance deed is normal at this scale and keeps the specification modest. Offering the road for adoption brings a different construction standard and a legal agreement, and the trade-offs are set out in our note on highway adoption at estate scale.

Parking provision follows the council's standards, and electric vehicle charging is now a building regulations requirement for new dwellings with associated parking, so show the charge point positions on the layout rather than leaving them to the contractor.

Street character and design coding

Five houses can look like a terrace, a courtyard group, or five unrelated buildings sharing a driveway. Officers will say which one they think they are looking at.

Give the group an internal logic. A limited material palette, a consistent approach to boundary treatment, window proportions that relate to each other, and a landscape structure that will still be legible when residents put up fences. Where the local plan or a supplementary document sets out design guidance, address it point by point rather than in general terms.

Set the buildings against the existing street. Building line, ridge heights relative to neighbours, plot widths and the rhythm of gaps all carry more weight on an infill site than the architecture of any individual house.

The choice between outline and full permission affects how much of this has to be resolved now, and our note on outline or full covers the trade-off. At five units, most applicants are better served by a full application, because the design is the argument.

Obligations and contributions on a small site

Section 106 obligations at five dwellings are lighter than on a major scheme but rarely absent. Expect the council to consider open space or play contributions where its policy applies at this scale, a management arrangement for any shared landscape or drainage, and occasionally a highway obligation.

Affordable housing is the variable. Outside designated rural areas, five units will normally attract no contribution. Inside them, the local threshold may bite, and an Affordable Housing Statement then has to address how the scheme responds.

The Community Infrastructure Levy applies where the authority charges it, and it is not negotiable in the way an obligation is. Check the charging schedule and the rate for the zone before the appraisal is finalised, and check whether self-build exemption is available for any plot.

A realistic document list

For a typical five unit site with no heritage or flood constraint, the submission usually comprises:

1. Application form, fee and ownership certificate.
2. Location plan, site layout, floor plans and elevations for each house type, and a street scene drawing.
3. Existing and proposed site sections where levels change across the site.
4. Planning statement covering principle, design, amenity, highways and drainage.
5. Drainage approach with percolation results and a maintenance proposal.
6. Preliminary ecological appraisal, biodiversity metric and gain plan route, unless exempt.
7. Tree survey to BS 5837:2012 where trees are present on or adjacent to the site.
8. Refuse strategy and swept path drawing.

Constraints add to this quickly. Flood zone 2 or 3 adds a flood risk assessment and a sequential test, a conservation area adds a heritage statement, and contaminated land history adds a desk study. Check the site before you commission anything, because the cost of finding a constraint in week nine is measured in months.

Enter your postcode on PlanScope to see which of the 66 report types a five plot scheme is likely to need.

This is general guidance rather than 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.