London Borough of Merton

How Merton decides on small housing schemes

Every decision on sites of nine units or fewer, coded from the council's own register and refreshed each quarter. What gets built, what gets approved, and what trips applications up.

Last updated April 2026 407 applications tracked Window: Jan 2023 to Mar 2026 5 areas, 6 scheme types

Applications logged

407

Full, householder and minor resi since Jan 2023

Decided so far

350

221 approved, 129 refused, 1 withdrawn

Approval rate

63%

Just over half of decided applications

Typical time to decide

11 weeks

Median determination time across all small sites

Merton, area by area

Colour shows how often applications get approved. Numbers show how many were decided. Hover or tap an area for detail.

Spotlight

Wimbledon

Decisions

108

Approved

Refused

Approval rate

83%

Hover or tap any tile to see that area’s detail.

Tile positions are schematic, not to geographic scale. Each hex represents one of Merton’s sub-areas as defined in the council’s own planning framework.

Wimbledon approves 83% of applications. Mitcham, closer to 45%. Same borough, same policy, 38 percentage points of difference.

Which kinds of schemes get approved?

Bar length shows how many of each type were decided. The split shows the share approved versus refused. Conversion is by far the most common route in Merton, but it's end-of-terrace that sees the highest approval rate.

Approved Refused Bar length = sample size (max n=136)

Conversion

61%n=136

Demolish & rebuild

67%n=89

Mid-terrace

60%n=42

Extension

65%n=26

End-of-terrace

72%n=25

Backland

46%n=13

Scheme types with fewer than 10 decisions in the window are not shown here.

Conversion, dividing one home into flats

Demolish & rebuild, existing building replaced with new homes

Mid-terrace, insertion into the middle of a terrace

Extension, rear, side or upward additions creating a new unit

End-of-terrace, new infill at the end of a terraced row

Backland, new build on rear gardens or courtyard land

Why applications fail in Merton

Of every hundred reasons cited in refused decisions in Merton, design quality accounts for the biggest slice at 34%.

Design 34%

Unit 17%

Infrastructure 15%

Amenity 12%

Transport 10%

Design quality, bulk, massing, appearance 34

Unit sizes, below space standards 17

Infrastructure, access, parking, drainage 15

Amenity, overlooking, daylight, noise 12

Transport, parking, safety, access 10

Open space, loss of garden or green space 7

Policy, affordable housing, density targets 3

Other, mixed reasons 1

Flood risk 1

Read as: “Of every 100 reasons cited in a refusal, 34 relate to design quality.” A single refusal often names two or more reasons. Based on 94 reasons extracted from refused decision notices.

In Merton, what gets a scheme refused is usually how it looks, not how many homes it adds.

Is Merton getting busier?

Decisions per quarter have fallen since 2023, and approval rates have drifted upward over the same window.

Decisions per quarter

Approval rate (%)

Hover any bar or dot for exact quarterly values. The most recent quarter may be partial while pending decisions work through.

Interrogate the data yourself

Every figure on this page comes from Merton's own planning decisions. We publish the underlying data so you can check it, replicate our findings, or use it in your own tools. Verify against the council's planning portal before relying on any record, and tell us if you spot a problem.

Download the data (Excel) CSV

Decided small-site applications, 1 to 9 units. Planning-decision layer only: Energy Performance Certificate, Land Registry and case-officer fields are held back. Contains public sector information licensed under the Open Government Licence v3.0. Methodology.

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Data sources & method

Applications. Sourced from the Greater London Authority (GLA) Planning Datahub and Merton Council’s online planning register. Covers full planning, householder, and minor residential applications of nine units or fewer decided in the window shown above.

Decisions and timing. Outcomes and determination times are taken from the council’s published decision notices.

Refusal reasons. Extracted from refused decision notices that were publicly available. Not every refusal has a readable notice, so totals count all refusals but the reason breakdown covers only those we could read.

Scheme classification. Site types (conversion, demolish & rebuild, extension, and so on) are coded from application descriptions and drawings. Areas are mapped from postcodes and ward names using the council’s own sub-area definitions.

Update frequency. Refreshed quarterly. Next refresh: July 2026.

Nothing here is planning advice. Outcomes are historical and do not predict individual cases. Approval rates vary with site specifics, policy context, and case officer. For a read on a particular site, request a Red Line Review. See our Terms of Use for full details on how this data is compiled and the limits of its use.