At 9am on 15 June 2026, Epping Forest District Council stopped being able to decide its own major planning applications. Under section 62A of the Town and Country Planning Act, an authority that has more than 10% of its major decisions overturned at appeal can be designated by the government, after which applicants take those applications straight to the Planning Inspectorate. Epping crossed the threshold and was designated. It is in Essex, so it changes nothing on the ground in London. The principle is the part that travels: a council’s record at appeal is no longer a private matter between it and the inspector. It now carries a consequence the council can measure.
That is the backdrop against which a much quieter, London-specific clause starts to bite on 1 July. The §78c buffer designates nobody. It makes refusals in seven boroughs harder to sustain at appeal, the same currency Epping was just judged in.
In the seven days to 22 May, two well-resourced developers had London riverside towers refused. Berkeley’s 867-home Aylesham Centre in Peckham, refused on appeal on 19 May. Rockwell’s 28-storey Glassmill scheme on Battersea Bridge Road in Wandsworth, dismissed by the inspector a few days earlier. Both refusals leaned on heritage and townscape. Both schemes were going to put net new homes on the ground in a London the Mayor has, in writing, admitted is failing on its housing targets. Berkeley has said it is considering a judicial review.
The numerical backdrop arrived in the same window. Molior London’s Q1 2026 release, published in late April, records 2,103 private starts across the capital in the first quarter, against a Mayor’s-own implicit need of roughly 22,000 per quarter. It records 2,838 private sales in the same period, down from 8,586 in a single 2015 quarter. Standing stock under construction sits at 36,735 homes, against the roughly 225,000 the Plan’s own arithmetic implies is needed to sustain 88,000 annual completions. The structural-supply argument that the AMR21 fail-grade language from February pointed at has now materialised in the quarterly numbers rather than abated.
The seven-borough §78c trigger sits inside that picture, and on a much smaller scale. For most of the past eighteen months, the conversation about the 2024 NPPF reforms has been about the new standard method for housing need. That conversation matters strategically, but for the small-site applicant sitting in front of a refused application, the more practical change is one that has had almost no press coverage: a clause that quietly retires the old Housing Delivery Test buffer regime and replaces it with one that bites in seven specific London boroughs from 1 July 2026. Wandsworth, where the Glassmill site sits, is one of them.
The mechanic, set out in NPPF paragraph 78c, requires a council to apply a 20% buffer to its five-year housing land supply calculation where three conditions are met simultaneously: a housing requirement adopted within the past five years against the pre-December 2024 NPPF, an annual requirement that sits at or below 80% of the standard-method local housing need, and a 20% buffer not already triggered by the 2023 Housing Delivery Test result. Lichfields’ April 2025 analysis identified the London-wide cohort that lands inside all three filters: Barnet, Bexley, Brent, Merton, Waltham Forest, Wandsworth and Westminster. From 1 July, each of these seven boroughs must demonstrate not the standard five-year supply but five years plus a fifth on top, a meaningful increase that several of them will struggle to meet against current trajectories.
The third filter does real work. The 20% buffer is not cumulative, so an authority already carrying it from a poor 2023 Housing Delivery Test result gains nothing on 1 July. Several London authorities sit in exactly that position. Barking and Dagenham already runs under the presumption with the buffer applied. Newham scored 61% on the 2023 test and carries the buffer and an action plan. Greenwich came in at 48%. The Old Oak and Park Royal Development Corporation is buffered under its own local plan action plan. None of them appears in the seven, because for them the clause changes nothing. The seven are the boroughs for which the buffer is genuinely new.
Why the trigger matters for refusal defensibility
Where a council cannot demonstrate the required supply, NPPF paragraph 11d engages what officers and inspectors call the tilted balance: the presumption that planning permission should be granted unless the adverse impacts of doing so significantly and demonstrably outweigh the benefits. In effect, the balance of argument on appeal shifts toward the applicant. A refusal that would have been comfortably defensible at appeal under a five-year supply position becomes more contestable under a four-and-a-half-year supply position, and the cost-of-fighting calculation on the council’s side moves with it.
For sub-10 unit schemes this matters in a specific and measurable way. Small-site refusals are disproportionately determined at officer delegation rather than committee, which means the case officer’s read of the planning balance does most of the work. The same officer who would have refused a borderline scheme on amenity-impact grounds at the end of March may, by mid-July, find the inspectorate calculus harder to ignore. This does not force approvals. It raises the cost of refusing, most visibly at the marginal scheme.
What the data shows for the seven boroughs
The Perfect Scale dataset covers 2,800 small-site (1–9 unit) determinations across these seven boroughs in the 2022–2026 window. Refusal rates vary substantially:
| Borough | Determined | Refusal rate |
|---|---|---|
| Westminster | 389 | 19.0% |
| Bexley | 365 | 29.0% |
| Wandsworth | 551 | 30.3% |
| Merton | 320 | 38.4% |
| Brent | 622 | 53.2% |
| Barnet | 277 | 56.3% |
| Waltham Forest | 276 | 66.7% |
The buffer will not move every borough by the same amount. Westminster already approves 81% of small-site applications, so the tilt is unlikely to make a numerical difference there. The three at the higher-refusal end are the ones to watch. Waltham Forest, Barnet and Brent sit between 53% and 67% small-site refusal, exactly where a swing of three or four percentage points in the borderline-decision band would shift the achievability of a typical conversion-led or backland scheme.
Pre-1-July refusals are not a wash for an applicant in any of the three. But an application validated in late June, ready to go before the case officer in late summer, sits in a different appeal posture from the same application validated in February.
The wider 26-borough context
Not everything changes on 1 July, and the distinction is worth getting right. The seven boroughs above carry adopted local plans still within their five-year window, the condition that makes the buffer applicable. The other twenty-six sit in the opposite position: no borough plan adopted since 2021, and since March 2026 their five-year supply calculation already runs against the standard method rather than the London Plan figure, because the London Plan itself crossed the five-year line that month.
In practice the tilted balance has been quietly available across most of London since March, depending on each borough’s individual supply position. The 1 July buffer is the visible, dated, named version of a structural shift that has run in the same direction for months. So an applicant whose pipeline crosses the 33-borough estate should not wait for July. The planning balance has already moved, and the cases already in the system are where that recognition pays.
What to do with this between now and 1 July
A few moves follow. On timing, any application with a tight refusal/approval edge in one of the seven buffer boroughs is better validated in late June than early June where the choice is open, so determination falls inside the post-trigger window. On appeals, an applicant holding a refusal that pre-dates 1 July keeps the right to appeal under the post-trigger framework if the appeal itself sits after the trigger date, which lengthens the menu of viable strategies. And read any authority’s housing land supply position straight off its most recent Annual Position Statement before betting on a planning balance, because the 5YHLS number is what determines whether paragraph 11d engages at all.
The Perfect Scale dashboards for each of the seven boroughs publish the dataset that sits beneath the refusal rate quoted above: the area-by-site-type matrix, the design-quality vs. amenity-impact split of the refusal-reason data, and the determination-time distribution by decision route. For applicants weighing whether to push a marginal scheme before 1 July, those three numbers together are the empirical version of the question the buffer raises in policy terms.
Sources. Lichfields, “The buffers are back in town” (Feb 2025) and “The Presumption: a London focus” (Apr 2025) for the borough-specific list and the cohort filters. National Planning Policy Framework, December 2024, paragraph 78c, for the mechanic itself. Molior London Q1 2026 release (published late April 2026) for the 2,103 starts / 2,838 sales / 36,735 under-construction figures, as reported across the London property trade press. Berkeley Aylesham appeal decision (refused 19 May 2026) and Rockwell Glassmill appeal decision (dismissed mid-May 2026) reported by Property Week and Planning Resource, week of 19 May 2026. Epping Forest District Council section 62A designation, MHCLG Notice of Designation, effective 15 June 2026, for the major-application appeal-overturn threshold.
The method behind these figures, and the limits of the data, are set out in the methodology. Every borough’s underlying decisions are in the free borough dashboards.